I wouldnt worry about it. You have more trades then him and he states in the feed back that he backed out to sale it for more money. That shows he seems to just be greedy (well he did ask on boards how to shill). So I think you are fine. Dont sweat it.
Always looking for MJ-Lebron-Wade-Durant-Hill-Wall-Cousins-Bledsoe-Patterson-Orton-Meeks-Prince-Magloire-Nazr-Mercer-McCarty-Delk-Walker-Mashburn- Football-Cobb-Conner-Tamme