There is absolutely no way he's back. Period. Owner's run the show, AB has taken malcontent to a malicious level against the owner's club. Called out Kraft on personal affairs, called out the league based on current owner/NFLPA arrangements.
There is not a single owner that will ostracize their own franchise by bringing this guy in. He is totally blackballed. It will never be admitted, but he is done by the owner's choice. And he knows it. That's why his ego is saying he is done because he wants to be done.
On another note- I read that Pats absolutely do NOT have a legal leg to stand on in denying him the rest of his 10M bonus. So I'm sure AB is going to get the last laugh on the Pats on this one. And it serves the Pats right. They had no business bringing him in. They deserve to pay.