At POS, the order total in a transaction for a return is tracked in as a whole total, without strict method-to-method mapping of subtotals used from original payment methods (outside of linked refunds for credit cards). When creating a return, all relevant allowed payment methods used from orginating payments will be displayed for cashier return options. Once a subtotal is paid out on the return, the remaining balance options will still show all allowed originating payment methods for the return remaining balance. This idea is for the strict return enforcement for all payment method types, tracking per originating payment method total. 

Example: If a check is allowed to refund to either check or cash options, and a total is paid for by cash, card, and check subtotals- if the refund accounts for cash + check balance to be paid back by cash (as an allowed method); the remaining subtotal for the card originating balance cannot also be paid back by cash unless cash is set as an allowed return payment method for card also.