Dummy payment method

Content

Customers are paying via credit card for some AR Invoice, when AR is making a refund it is creating a invoice in AP, however that is not paid via system, it is settled outside system via CC Refund. and this invoice is cancelled in AP
this is creating an imbalance in credit card suspense account

now i need a dummy payment method to settle this via AP
two questions
1) what all required for this setup
2) how can we bypass entries hitting cash management, business does want to go CM