Walker's defense of "he thought he was engaged in an altercation" is alright I guess. I mean I thought they were going to fight. I don't think Ward expected it to happen as quick as it did as well. Maurice's comments were pretty out of place and disrespectful, and Rutherford's show a potential level of intent which is BS too.
All that being said, I still think it was a cheap shot, thrown with bad intent, and IMO should have been a match penalty. Sucks for Walker and the Canes though, I suspect someone will be after his head tomorrow, so we'll see.
Edit: Also pair that with Jokinen blatantly trying to hurt Chara as well, and I think we should be looking at a suspension or some penalty for the Canes, because both those plays, while the game wasn't even in question, were pretty blatantly obvious where the intent was.