What about this reason 
His negative feedback is not for cheating on bounty or scamming someone. Judge any feedback with the comment, not with the red tag and vice versa. He has done nothing bad which deserve a negative tag and that's why yahoo is allowing him in the campaign. His reputation is +4 in my view so there's nothing wrong why yahoo will check that account profile. Most of his negative feedback is just a retaliatory feedback for his previous action.
Only a DT feedback can give him a negative feedback and in his case, There is no solid reason why he will receive one. If you really believe that this guy done a serious thing that worthy to receive negative trust.
Try to open a thread on Reputation section about that matter and let DT members judge whether to give red paint or not. I'm not a DT so my opinion about his has no weight in this case.
