Honestly, neither of the negative feedbacks really means much since you aren't on DefaultTrust and you have no particular reference to what happened. The only reference is you defending a known scammer named 'Bono'?
Instead of escalating the situation and trying to get people to leave him undeserved red, you could easily resolve the situation with him. Mutually deleting the negative trust would have squashed it all but you wanna push it cause of ego?
1) I once traded with someone named 'Bono' and he didn't scam me. So I left positive feedback. When he was being accused of scamming, though, I asked for concrete proof because I had dealt with him personally and he wasn't a total asshat at the time. Once it became apparent he was scamming others, I left negative feedback.
2) I am not pushing anything due to ego. He abused the trust system by posting lies about me. Mutually deleting
actual negative reviews off of his profile would just be rewarding bad behavior.
Yeah, that's the long and the short of it

I'll just keep this thread handy in case I'm ever questioned.
Zank you Bitcointalk!