Thanks for addressing.
Quick answer - not that I see. Based on the facts relayed, you are a participating provider for certain insurers. You have patients that are members of that insurer coming to you for treatment. You want to offer a covered service, but be compensated fee-for-service from the patient. Well, we would all like to have our cake and eat it too, but not going to happen here. By contracting with the insurance company you are obligating yourself to treat that insurer's members for covered services at the fee schedule rates. You are also contractually obligating yourself to accepting the insurance fee. I do not see any way around this. If you start asking for cash from patients for this new service there is the potential an insured will report you and you may be seeking charges of insurance fraud or other related allegations. Best to skip it. If being compensated as a non-par doc is that important, prior to requesting out of pocket payment you should consider terminating your insurance contracts, which I know for many would open another can of worms.