You don't resign from the Mob. There is no such thing,

They are displayed having a twisted sense of honor, 'taking no crap from anyone,' with easy access to women and money. Such displays romanticize organized crime and, as an unintended consequence, serve to perpetuate the phenomenon and create alluring myths about the Mafia.

It's possible that John Gotti has decided that he doesn't want to commit any more crimes. But if whoever now runs the Gambino family says, 'We've got something important for you to do', and he doesn't do it, he's a dead man.

The mob has many heads, but no brains

A mob is a group of persons with heads but no brains

The five directors cannot be forced to resign; hence there is no vacancy to which new PCGG directors can be elected.