Wow, this is quite a mess for you! I'm afraid the only way out is going to be a bit of paper work. It sounds like you are going to need to get an NPI number that will belong to the Dr but for the tax ID & location of the nursing home. However you cannot do that the way things are because the NH (& it's tax ID #) already have an NPI and like you said, Medicare will not allow you to sign up a Dr under the NH. So if the dr got a new tax ID number, just for his NH visits, then applied for an NPI number under the new tax ID & 'group' then you would have to apply for a Medicare # for the group (855B) & for the dr at the NH location (855I) and an 855R to reassign the benefits. If the Dr's private practice is under a group name, and not the Dr's personal name, he could apply for a tax ID under his name, then he wouldn't have to complete the 855B or the 855R. Their is still a problem with Medicaid. In order to resolve that you need to get either his private practice, or his 'new group' to become a medicaid group provider. That way, when he bills for whichever location becomes a group, he bills under a group medicaid provider # for the payment info. Then he can use his individual number for the other location. I hope you can follow this.
My brain hurts.
Michele