I can somewhat agree with your position except for his email to the employees of United.
Yes in retrospect he did perhaps go out on a limb early on. Which does make me wonder if he had perhaps been led astray. Not saying this did happen, just wondering.
Agree always dangerous to only get one side or part of the story before declaring your position - and when you can't be sure what the investigation will reveal.
But the 24/7 news cycle and social media puts a lot of pressure to respond quickly. You simply have to trust you are being well informed. It can be a case of damned whatever you do. Imagine if he had criticised the crew and then found pax was at fault.
In politics you usually don't survive if you have led the boss astray - I think you guys recently had a senior government figure (NSA) resign over this.