I wonder how often these things ever truly "heal"? In my work experience, if a manager "loses the room", it's likely s/he has lost it forever. Mostly because it's rare for adults to truly change very much. We might make a concerted effort to meet a certain deadline, or appreciate a new habit of pizza lunches, or whatever adjustment, in the short term. Long term, though, nobody forgets what went before. And the manager usually reverts to form eventually.
But anyway, I would say if anybody was going to be aware of any imminence of Hynes "losing the room" it had better be Poile. And if Poile ever became aware of this, I don't think he could have kept Hynes around. That's a point of no return. I also don't know how you "almost completely" lose the room. You lose it or you don't. If any significant number of players/team leaders have started to have doubts, it's already lost. Otherwise you maybe have one or two malcontents instead of it being a case of "losing the room"? There's usually one or two malcontents in any group.