I don't completely agree, very grey area you are talking about here.
He gets hit into the boards and falls down. When watching the play live, you expect he was fallen by the check, not by the fact he could not put pressure on his leg. A ref will not call the play down at this point.
He spends 3-4 seconds on the ice before he stands up with all weight on the other leg and begins to attempt to hop out of the zone, but within a couple seconds the puck is in the back of the net.
There is no obvious moment during live play that the ref has an opportunity to call the play dead with 100% certainty. Only if the puck had changed possession or Bolland remained on the ice immobile would that have happened.
In hindsight, when you look at the replay and know the severity of the injury, sure you can make any argument you want. But at the time of the play, there was no certainty for the ref to stop the play.
I speak from experience in having sustained both an Achilles tear and a MCL tear. Actually, since I don't want surgery on my knee, I'm still suffering from the effects of the torn ligament (partially torn).
I recognized the sign of a structural problem with the leg when I watched the replay of him putting weight on the left leg, stumbling down and immediately taking the weight off. I remember how I reacted when I tore my Achilles. I drove home using the damaged foot because I could put some pressure on it, but couldn't stand up on both legs. It didn't hurt as much as it was numb, and when I first stood up, my leg gave out.
I understand that it's not a call the ref wants to make. If he blows the play dead and the player isn't actually injured (hurt and injured are distinct), then he looks like an idiot. But the responsibility is to ensure the safety of the players and in doubt, the conservative should take precedence right? Just like the tie on the new icing.
When in doubt, do the thing that is safest.
It was probably not going to change the outcome. The team, although I didn't watch the game itself, didn't seem like they had anything. They weren't looking particularly threatening offensively and ended up scoring 0 goals.
You are not winning with 0 goals, and honestly, there isn't much to convince anyone that they would have scored had the refs stopped the play and prevented that 2-0 goal.
Does not excuse that lapse in judgement.