Why is the payment processor so strongly coupled to the point that you would need to rewrite it? I understand there's effort to adapt it but I don't think it's good to write the code like that.
Well, of course some things are going to need to be rewritten? It won't be complicated at all, but the primary concern is registering new accounts, looking through documentation for API keys, testing, etc. This seems like wasted effort just to get banned again. Or worse -- get banned and account funds put on a hold.