There is absolutely no way for any adjustment on the credit card transaction. Each sale or refund is unique. There is an authorization code that appears on each CC transaction...it is the validation electonically of that singular action. All account info is x’d out (save for the last four digits of the CC account...there is no revisiting the transaction.
That information is only x’d out on the receipt, to keep someone from picking the receipt out of the trash and using the full card number to make purchases online or over the phone. The merchant’s records, as well as the card processor’s, include the full card numbers and verification information.