... the patient has Workers Comp insurance for anything related to his back (our claims are not) but that is what Medicare has as the patient's primary insurance ...
To repeat: the problem is that Workers Comp is listed as primary insurance with Medicare. It shouldn't be listed with them at all. The patient should contact Medicare and have them list as primary whatever other insurance they have outside of Workers Comp. The patient has to do this. Medicare will not respond to a request from any other party.
Our experience is that Medicare does not ever pay as secondary on a Workers Comp case (I realize that maybe this is different in other MAC jurisdictions?). We don't ever bill Medicare as secondary on a Workers Comp case.