If he slashed him why didnt the ref react? or hand out a 10 minute gross misconduct with a game?
"Gross misconduct" as a penalty type has been removed from the NHL rules (but it's still in place in Hockey Canada rules). I would guess that it was removed because it was considered redundant, being effectively very similar to a game misconduct (actions that formerly incurred a gross misconduct now incur a game misconduct instead). But it did remind me of a tangent I was thinking about last night in terms of the effective difference between a game misconduct and a match penalty. Either one results in the player being kicked out of the game, but a match penalty automatically awards a 5-minute power play to the non-offending team (barring additional penalties on the play). In practice, many actions that would also get you a game misconduct incur a major penalty as well (however a game misconduct for abuse of officials is not one of them), therefore having the same effect as a match penalty, at least within the game.
The difference lies in how things are handled after the game. USA Hockey has a clear answer.
Game misconduct: automatic suspension of at least one game (longer if it's not your first game misconduct penalty of the season - the suspension is equal to a number of games equal to the number of game misconducts you have received in the same season). No automatic disciplinary hearing. I think there might have been something like a disciplinary hearing if you got a third in the same season, but don't remember.
Match penalty: automatic indefinite suspension pending a disciplinary hearing. The disciplinary hearing can result in a longer suspension, or they can rescind it.
I'm not entirely sure what happens in the NHL, other than that a game misconduct itself is not an automatic suspension (with an exception like if it's for "abuse of officials" then it carries an automatic 10-game suspension, which can be made longer if deemed necessary or maybe reduced on appeal). It's probably something like that DOPS is not required to even look at it if it's a game misconduct, but they are if it's a match penalty. In practice, if you get either one, there's a good chance you'll hear from DOPS anyway.
Gross misconduct from a Hockey Canada game? No idea.