If you don't give him credit for that, what would you give him credit for? If he stopped Carreyrou, you'd obviously blame him. Therefore in order for your judgement to be meaningful, you have to admit that him allowing Carreyrou to go ahead and topple the house of cards was a good action. Otherwise no matter what he does you judge him negatively - and in that case, your decision is predetermined and not of informational value for anyone.