I don't know, it seems like if the corporation sent a high fee transaction they have already been alerted that their defenses need to be raised. so your attack

I don't know, it seems like if the corporation sent a high fee transaction they have already been alerted that their defenses need to be raised. so your attack vector has limited efficacy as it might be closed. the hackers need to have the foresight to sit in the server and accumulate other blackmail, but also not lose the chance to take the bitcoin bounty based on another hacker finding it.