If the Bounty Manager knew that the project is scam and still promoted it than they deserve a negative trust.
But if they didn't knew about that, they are no different from bounty participants as they get paid to advertise.
If bounty manager are to be given negative trust for working on a scam project, bounty participants too deserve one as they too promote for payment.
I think the tag should only be limited to the managers and not to the participants because the participants are mostly are innocent to this. Its should be the bounty manager's responsibility who take the lead and guidance to the workers in which they should review it carefully the ICO before accepting it because their reputation is at stakes. I just hope we could provide a list of bounty managers reputation so that the workers specially the new comers could be aware.