Billing for service in different state

A client in MS. requested a group Medicare PTAN and reassignment of providers so she can bill the G0179 & G0180 codes for and I am copying her email so I do not mess up the wording:

the nurses do not make nursing home calls, nor do the physicians....we actually need the La Medicare # due to a number of Home Health Agencies throughout the State of La. that the physicians order Home Health services for...but the only thing the physician does is sign/review the certifications/re-certifications that the Home Health nurses bring to the clinic, maybe change meds, orders, etc. The Home Health Agency Name & address has to appear in block 32a (or Loop???) on the HCFA 1500 form......I bill G0179 or G0180 for these.......

This provider group currently has a MS Group PTAN and the providers are reassigned to the group and she currently bills these codes for patients in MS. LA uses a different intermediary – MS is Cahaba and LA is Pinnacle.

My brain is trying to figure out how to complete the 855B section 4, since the providers are in MS, not in LA – but the patients are in LA. Do I complete section 4A, with the MS address of where the providers are? If I do that, wont the intermediary say”this is not in LA so you need a MS PTAN”? Do I complete section 4D, for rendering services in patient’s home for the state of LA... even though the providers do not actually see the patients in the home?

I called Pinnacle to get their take, and now they are saying since it involves Home Health Agency, I need an 855A – but the charges are for the physician services and in MS we use our Part B group PTAN and the individual PTAN on the HCFAA.

Am I over thinking this? Any help you can throw my way is greatly appreciated.