I wouldn't be surprised if he comes back under another name.
Ha ha. This is generally what happened and I think every scammer do this. Even Maybe still he is managing bounty with some other accounts. And reading this thread everyday. We can not stopped them completely. They will come again and again. If project owner take action then they can do something different.
I think this kind of scam occurred for project owner. Because all the owners need to choice a trusted manager for managing or for promoting their project. In this forum so many trusted persons are available and they never scam. Most of the owners think about the monthly payment for managing a project. For this they choose that manager who offered low payment for management. I think owners need to pay some more and choose trusted people for their project. Then i think this kind of situation will never happen again.