What he accuses the other user of is complete nonsense, since even if he warned someone about something, it was correct, but since Royce at some point had a lot of red marks. Any adequate project would refuse to cooperate with such a manager in order to maintain its reputation.
Very very easy to handle, if a manager thinks he is accepting any negative or neutral feedback participant then he should go ahead, but if it appears that they don't have interest in accepting such user then there's no need to bother accepting them and later requesting for them to get rid of their trust tags, i think every campaigning organizations also have their own set rules and taste when it comes to offers for participation in their campaign.