A psittacosaur with Feathers?

Can feathers be considered a synapomorphy of any group of animals at all? It used to be thought that birds alone possessed feathers. This was until a number of chinese dinosaurs were found to bear filamenous structures and even long true feathers in some other forms. So ok, a synapomorphy of the higher coelurosaurs? Maybe not even a synapomorphy of theropods or even saurischians. Dr. Michael Caldwell revealed to his Paleo 318 class today that a well renouned fossil dealer had approached both him and Phil Currie with a psittacosaur which he had purchased at the world famous Tucson Rock, Mineral and Fossil Expo, which appeared to bear featherrs. Dr. Caldwell is scepticle that the structure are in fact true feathers and instead called them epidermal extensions. I imagine that Dr. Currie is rather sceptical because of his recent encounter with a forged fossil. He had supported a fellow paleontologist who purchased a fossil at the same infamous show purporting that it was an even mix of dinosauriand and bird features. the fossil turned out to be an actual mix of bird and dinosaur fossils from separate animals, thereby causing alot of academic grief for Currie. Kevin Aulenback who preped the fossil had been quick to point out the error and unfortunetly also received much grief and has since transitioned to paleobotony so that he wouldn't have to deal with the politics of Vertebrate paleo. I for one am willing to believe that any scenario could be true at this time since I haven't actually seen the specimen. In fact, all that Caldwell has is a photo. Hopefully i'll be able to procure a copy of the photo for this site and I will try to provide as full a description as I can on the basis of what is visible. However, this means that if I can argue that it is a new species, then I will be able to name it without ever actually seeing the real specimen. Since I will be the first to publish on it. However I will refrain from committing this academic suicide as nobody will be willig to share anything with me since they'll only see that I steal their research.
The issue of the feather also begs the question, could this fibrous epidermal covering be ancestral to all the dinosaurs and their immediate relatives. At least one pterosaur has been found to have some kind of "fury" covering. So if the outgroup to dinosaur even has this covering, how far back might it go. This is of course wild conjecture. There is a pretty good chance that the covering evolved multiple times in order serve in thermo regulation. Keep in mind that an animal in the deserts of mongolia might have used feathers to stay cool, not just keep in body heat.