Looks like certainly lost his balance awkwardly which made the second big of contact take him down.

As others have pointed out, the initial crosscheck is a pretty common move by opposing centermen that lose a face off. The intent is to clear out the slot to give your goalie a good line of sight to the puck. By crosschecking the body of the opposing player, you are keeping it “clean” and usually avoid a penalty call. Were it not for the blood, I don’t think that even gets called a penalty 9 times out of 10.