Royalties reporting

I've used the Payments by Performance report in the past, however, I was looking over the code and in the SQL of the procedure, it's looking like the Tess writer says "this isn't an exact science".  I wrote my own procedure to get payment methods (for our theatre's calculation of royalty payments), however, exchanges seem to be the cursed rows of data I cannot secure the original payment method on.

Does anyone have a way of pulling the original payment method on an exchanged ticket?

Thanks!

RJ