In my opinion, this technique is poorly demonstrated, dude, for two reasons.
First, why in the world would an opponent playing butterfly guard break the guy down with the head like that? It doesn't make any sense as generally you want to be sitting up when you are playing butterfly guard and the top guy would love to smash you down with his head in your solar plexus.
Second, not once does the guy on the bottom in your video actually play x-guard correctly. The knee from the top hook in xguard needs to be past the opponent's groin to really utilize it as a hook.
Nothing personal, but this looks sloppy man - not the level of detail that I would suggest you post on this forum as it just looks bad. If you're teaching a counter to a move (such as xguard), you can't show it with your partner doing things that are just wrong.