Well by that reasoning, if I go out with my car and rear end someone because I accidentally hit the gas instead of the brake, that must mean I get off scot free as well - even if I break someone's neck in the process?
I think you're mistaken. The video clearly shows Williams stick hitting Saku in the face and blood oozing from the eye area afterwards. That's all you need, whether it was intentional or not - Williams is at fault. And if you watch the video tape, you can see that Williams isn't paying attention to where his stick is going either.
And if you want to fine or suspend Komisarek too that's totally fine by me too. The NHL players are way too cavalier about how they handle their sticks and it's going to take a career ending injury, or a few, for the league to crack down.