What's criminal about selling to Zerodium though? I guess a case could be made that selling on the darknet is 'not in good faith'. That is an important criteria

What's criminal about selling to Zerodium though? I guess a case could be made that selling on the darknet is 'not in good faith'. That is an important criteria for determining if you're aiding and abetting where I'm from. But this problem is not there with all avenues for grey market transactions.