What a mess.
GM may be a problem, I don't think he's the cause, that lies firmly with the players.
He is certainly adding fuel to the fire by washing the changing rooms dirty laundry in public though, that I don't like, he should stfu.
The last time this happened imo it was called an injury crisis where so many players were getting injured during training, again player power at play.
Given time Bruce would have had to face this also, as would any new manager coming in.