I would recommend to hire experienced bounty manager
Hiring a manager seems like an awesome idea but what bothers me is that this way you, probably, won't learn how to do things yourself. I'm also curious about the issue OP mentioned and it would be really helpful if someone could explain a bit more, what are the functions of bounty manager? Basically, he's gonna control the whole thing in all the social media and all the participants? That seems like a lot of work for just one person..