I am pretty sure a lawyer could be found that would happily take that case against the board. And that Altman would be quite willing to go that far. At least I would not have staked my professional life and personal economy on it not happening.
PG called it over 15 years ago: "You could parachute him [Sam Altman] into an island full of cannibals and come back in 5 years and he'd be the king".