It is not Karpeles fault that a criminal is trying to sell your data. The perpetrators of crime are the criminals, and in this case MtGox & its customers are the victims. In fact, if someone hadn't been defrauding them via the malleability exploit, we wouldn't be in this situation.
Plain and simple: If your service can get hacked, it is your fault. Period. Nobody's accusing him of being a criminal because of that, but if you can't keep your users data safe, you deserve their resentment.