The Rizzuto's are done, and Vito knows it too.

My guess is that any guys that were loyal to Vito and the Rizzuto Family were informed they were under new management by the "new regime". They were also told where, when and how much money to start kicking up to their new boss(es). Otherwise, these guys could join Nick, Nick Jr., Paolo Renda and Agostino Contrera.

There are guys out there still running their rackets and drug smuggling, but they are kicking up to the new Montreal boss(es).

I think it also likely that Vito knows who the new regime is, and who is responsible for the murders of his family members. Vito's wife or some other family member very likely heard from a Rizzuto soldier or associate and told during a visit at the SuperMax in Florence.

I do believe that Vito will be extradited to Italy to face charges there when he finishes his time in the US.

If he is not extradited, I don't think he can, nor do I think he will, try to exact revenge.