I would.

There are many prominent rats who have dropped out of the WPP and are living in the open.
The 5 families appear to have a non official policy of not hitting turncoats. At least after the damage has been done. It's apparently not worth the resultant heat from LE.
Now this isn't discounting a young Turk going off the reservation, but in as so far as a Gambino family sanctioned hit? No way. Maybe if Peter Gotti was still running the ship. But the Gotti's and their supporters are no longer a power within the family and the current power bloc, I doubt, would hardly give two shits, let alone risk prosecution for a hit.

I would doubt he'd ever move back. There's nothing there for him. He'll want to live out his few remaining somewhere warm judging by his health.