The rule has screwed the Caps before, too. It sucks on so many different levels.
I'm not totally opposed to being able to challenge based on off sides. If a team scores on the rush and the play should have been dead, that is a reasonable challenge. But there has to be some cut off.
Just look at this. The goal is 20 seconds into the video and the clip starts after the missed off sides call. This kind of thing damages the integrity of the game.
It's also very silly to me that we're all watching the play resume like nothing happened. We're literally watching shots/hits/saves/etc. that will be have to be removed from the score sheet. It was all a big nothing and we could have just left the room.
If you're gonna stop the play and make a ruling, its should happen within a few seconds, like goalie interference calls are. Otherwise move on. No take backs. This ain't preschool.