I think Bruce winning rubs it in less to Don/Cam and more to Debrusk/McAvoy and all the other players who mutinied to get him fired.
I doubt it.
Players play.
Managers manage.
Who knows if Butch could have facilitated another Cup

run and, possibly, a championship

.
My understanding (between the lines of comments by the Herald's Steve Conroy) is that Sweeney assured Cassidy all was status quo & that Bruce would be back the following season.
Neely got wind of exit interview whining and -- stop me if you've heard this before -- inserted himself into the situation, dictating Cassidy must go.
Hence Sunny Jim.
Hence, at least in part, the mess that ensued.
You know who must go?
Bam Bam Cam, that's who.
Recall that Neely issued a shot across the bow if not a veiled threat to Claude Julien's job security when averring that the Bruins "can't win if they don't score," or words to that effect. (This during the 2011 Cup year.)
It would not surprise if Neely was behind the Get Big & Nasty trend in general, which I enthusiastically supported, and, in particular, the signing of Nikita Zadorov.
(Interestingly, #91, loose cannon with potential leadership chops, recently threw a bit of shade, if not a gauntlet, management's way by publicly questioning whether the front office would allow #88's prime years to go to waste.
(Most un-Bruins like. A raised eyebrow in this corner. The times they are a- changing.)
Sweeney is problematic.
On balance, Neely is the greater problem.
Sooner or later (later, naturally) he must go.