It is possible to include Custom Event Fields through the Report Center version of the Payment Details report.

To do this you must

1. Navigate to Control, Report Center.
2. Expand the Billing group.
3. Choose the Payment Details Report.

4.  When building the report, you may include Custom Event Fields when filling out the Choose Data section.
5.  Scroll to the bottom of the Choose Data segment.
6.  Expand All Custom Fields, then Custom Fields.
7.  The Custom Event Fields will be listed here.
8.  Include the fields desired by checking the box next to the field name.

9.  Finish out the report as desired.

Built this way, you can include Custom Event Fields in a Payment Details Report.