El tipo varian es COleVariant y aqui te envio una funcion que convierte de COleVariant
a CString talves te sirva:

CString Variant2String(const COleVariant& var){   // Copiado de clase CCrack en DaoView
        CString strRet;
        strRet = _T("Fish");
        switch(var.vt){
                case VT_EMPTY:
                case VT_NULL:
                        strRet = _T("NULL");
                        break;
                case VT_I2:
                        strRet.Format(_T("%hd"),V_I2(&var));
                        break;
                case VT_I4:
                        strRet.Format(_T("%d"),V_I4(&var));
                        break;
                case VT_R4:
                        strRet.Format(_T("%e"),(double)V_R4(&var));
                        break;
                case VT_R8:
                        strRet.Format(_T("%e"),V_R8(&var));
                        break;
                case VT_CY:
                        strRet = COleCurrency(var).Format();
                        break;
                case VT_DATE:
                        strRet = COleDateTime(var).Format();
                        break;
                case VT_BSTR:
                        strRet = V_BSTRT(&var);
                        break;
                case VT_DISPATCH:
                        strRet = _T("VT_DISPATCH");
                        break;
                case VT_ERROR:
                        strRet = _T("VT_ERROR");
                        break;
                case VT_BOOL:
                        return strBOOL(V_BOOL(&var));
                case VT_VARIANT:
                        strRet = _T("VT_VARIANT");
                        break;
                case VT_UNKNOWN:
                        strRet = _T("VT_UNKNOWN");
                        break;
                case VT_I1:
                        strRet = _T("VT_I1");
                        break;
                case VT_UI1:
                        strRet.Format(_T("0x%02hX"),(unsigned short)V_UI1(&var));
                        break;
                case VT_UI2:
                        strRet = _T("VT_UI2");
                        break;
                case VT_UI4:
                        strRet = _T("VT_UI4");
                        break;
                case VT_I8:
                        strRet = _T("VT_I8");
                        break;
                case VT_UI8:
                        strRet = _T("VT_UI8");
                        break;
                case VT_INT:
                        strRet = _T("VT_INT");
                        break;
                case VT_UINT:
                        strRet = _T("VT_UINT");
                        break;
                case VT_VOID:
                        strRet = _T("VT_VOID");
                        break;
                case VT_HRESULT:
                        strRet = _T("VT_HRESULT");
                        break;
                case VT_PTR:
                        strRet = _T("VT_PTR");
                        break;
                case VT_SAFEARRAY:
                        strRet = _T("VT_SAFEARRAY");
                        break;
                case VT_CARRAY:
                        strRet = _T("VT_CARRAY");
                        break;
                case VT_USERDEFINED:
                        strRet = _T("VT_USERDEFINED");
                        break;
                case VT_LPSTR:
                        strRet = _T("VT_LPSTR");
                        break;
                case VT_LPWSTR:
                        strRet = _T("VT_LPWSTR");
                        break;
                case VT_FILETIME:
                        strRet = _T("VT_FILETIME");
                        break;
                case VT_BLOB:
                        strRet = _T("VT_BLOB");
                        break;
                case VT_STREAM:
                        strRet = _T("VT_STREAM");
                        break;
                case VT_STORAGE:
                        strRet = _T("VT_STORAGE");
                        break;
                case VT_STREAMED_OBJECT:
                        strRet = _T("VT_STREAMED_OBJECT");
                        break;
                case VT_STORED_OBJECT:
                        strRet = _T("VT_STORED_OBJECT");
                        break;
                case VT_BLOB_OBJECT:
                        strRet = _T("VT_BLOB_OBJECT");
                        break;
                case VT_CF:
                        strRet = _T("VT_CF");
                        break;
                case VT_CLSID:
                        strRet = _T("VT_CLSID");
                        break;
        }
        WORD vt = var.vt;
        if(vt & VT_ARRAY){
                vt = vt & ~VT_ARRAY;
                strRet = _T("Array of ");
        }
        if(vt & VT_BYREF){
                vt = vt & ~VT_BYREF;
                strRet += _T("Pointer to ");
        }
        if(vt != var.vt){
                switch(vt){
                        case VT_EMPTY:
                                strRet += _T("VT_EMPTY");
                                break;
                        case VT_NULL:
                                strRet += _T("VT_NULL");
                                break;
                        case VT_I2:
                                strRet += _T("VT_I2");
                                break;
                        case VT_I4:
                                strRet += _T("VT_I4");
                                break;
                        case VT_R4:
                                strRet += _T("VT_R4");
                                break;
                        case VT_R8:
                                strRet += _T("VT_R8");
                                break;
                        case VT_CY:
                                strRet += _T("VT_CY");
                                break;
                        case VT_DATE:
                                strRet += _T("VT_DATE");
                                break;
                        case VT_BSTR:
                                strRet += _T("VT_BSTR");
                                break;
                        case VT_DISPATCH:
                                strRet += _T("VT_DISPATCH");
                                break;
                        case VT_ERROR:
                                strRet += _T("VT_ERROR");
                                break;
                        case VT_BOOL:
                                strRet += _T("VT_BOOL");
                                break;
                        case VT_VARIANT:
                                strRet += _T("VT_VARIANT");
                                break;
                        case VT_UNKNOWN:
                                strRet += _T("VT_UNKNOWN");
                                break;
                        case VT_I1:
                                strRet += _T("VT_I1");
                                break;
                        case VT_UI1:
                                strRet += _T("VT_UI1");
                                break;
                        case VT_UI2:
                                strRet += _T("VT_UI2");
                                break;
                        case VT_UI4:
                                strRet += _T("VT_UI4");
                                break;
                        case VT_I8:
                                strRet += _T("VT_I8");
                                break;
                        case VT_UI8:
                                strRet += _T("VT_UI8");
                                break;
                        case VT_INT:
                                strRet += _T("VT_INT");
                                break;
                        case VT_UINT:
                                strRet += _T("VT_UINT");
                                break;
                        case VT_VOID:
                                strRet += _T("VT_VOID");
                                break;
                        case VT_HRESULT:
                                strRet += _T("VT_HRESULT");
                                break;
                        case VT_PTR:
                                strRet += _T("VT_PTR");
                                break;
                        case VT_SAFEARRAY:
                                strRet += _T("VT_SAFEARRAY");
                                break;
                        case VT_CARRAY:
                                strRet += _T("VT_CARRAY");
                                break;
                        case VT_USERDEFINED:
                                strRet += _T("VT_USERDEFINED");
                                break;
                        case VT_LPSTR:
                                strRet += _T("VT_LPSTR");
                                break;
                        case VT_LPWSTR:
                                strRet += _T("VT_LPWSTR");
                                break;
                        case VT_FILETIME:
                                strRet += _T("VT_FILETIME");
                                break;
                        case VT_BLOB:
                                strRet += _T("VT_BLOB");
                                break;
                        case VT_STREAM:
                                strRet += _T("VT_STREAM");
                                break;
                        case VT_STORAGE:
                                strRet += _T("VT_STORAGE");
                                break;
                        case VT_STREAMED_OBJECT:
                                strRet += _T("VT_STREAMED_OBJECT");
                                break;
                        case VT_STORED_OBJECT:
                                strRet += _T("VT_STORED_OBJECT");
                                break;
                        case VT_BLOB_OBJECT:
                                strRet += _T("VT_BLOB_OBJECT");
                                break;
                        case VT_CF:
                                strRet += _T("VT_CF");
                                break;
                        case VT_CLSID:
                                strRet += _T("VT_CLSID");
                                break;
                }
        }
        return strRet;
}