It doesn't mean much, but I tagged the guy for doing that.  Account farming is responsible for a large part of why this forum is going down the toilet.  Shitposting, scamming, etc. 

OP, why are you so concerned that he didn't get a neg?  DT people don't routinely tag account sellers, so I would say most of them have trust that's clean.  Plus he and many others create throwaway accounts to do their deals with.  Neg trust is appropriate but seldom helps.