So, the thing about having enforcers around to keep the rats and dirty players in line runs into two different problems that haven't been mentioned in this thread yet.
The first is the fact that the other team probably would have had an enforcer too. So sure, in theory, if "Rat" takes a cheap shot at someone on "Team 1", then "Enforcer 1" goes to address it. Thing is, then "Team 2" also has an enforcer, who we'll call "Enforcer 2". So, Rat just hides behind Enforcer 2, and then Enforcer 1 fights Enforcer 2, meanwhile Rat doesn't get so much as a scratch, and thus get's to keep being a dirty player.
The second problem is that the notion of "enforcers keep guys in line and protect the code" is clearly relying on intimidation. Now here's the thing about intimidation: its an extremely binary tool. By which I mean, intimidation doesn't really serve any purpose if it doesn't accomplish its primary purpose. This is especially true in any sport where violence is either allowed or is the whole point. Whether its hockey or its boxing, if you try to scare your opponent into behaving or competing a certain way, and your opponent isn't intimidated by you, then any effort and time that you put into trying to intimidate them is entirely wasted.
Simply put, intimidation either works, or it doesn't. Now I know someone is going to be tempted to be a smart ass and say "well, duh, everything either works or doesn't work!" But what I mean is that intimidation doesn't really have a gradient of success. Think of it like a math test that only has a single question, which is only worth a single point. In that case, there are two options. You either get 1/1, and so score 100%, or you get 0/1, and so score 0%. There isn't really any middle ground.
Compare this to, say, body checking, which DOES have a gradient of success. Sometimes you try to hit a guy, and either miss or just bounce off, failing entirely. Sometimes you bump him and he loses puck control a bit, and now the pair of you battle for it. Sometimes you pin him along the wall and, again, you have to battle for the puck. Then, sometimes, you just run him completely over, knocking him to the ice, and entirely separating him from the puck.
Given that intimidation is unreliable and highly binary in its effectiveness, and Kassian would probably have had a goon of his own on his team too who would step in and fight for him against the other goon, then I'm going to say that no, Enforcers wouldn't have prevented the kick. Kassian having some discipline and controlling his temper would have prevented the kick.