Montreal's terrible off-season was due to Price & Weber retiring rather than anything having to do with KK.
The only move Montreal did due to that was trade for Dvorak, which was a bad move.
The Carolina situation had little to do with that summer. Weber, Price, Byron, Edmundson were all hurt. Danault & Tatar left as UFAs. KK left after all of that had already occurred.
He should have rebuilt that summer, but he didn't because he definitely thought Price was coming back. Price reported to camp then went into NHL player assistance program forcing Montreal to pick Montembeault off waivers. Price essentially retired after that season.
The Mailloux pick, the terrible start that Bergevin kept doubling down on (I believe in this team crap), the fact Montreal was getting worse during his tenure all led to his firing.