There's pretty extensive evidence of an attempt to impersonate him here. There's also a lot of stuff that's alarming from a philosophical standpoint for anyone involved with privacy/anonymity - a link to an "ioerrror" (instead of "ioerror") github is a clear attempt to deceive, and it's deeply questionable to do to visitors to the site, independent of any effects on Appelbaum.
It's pretty obvious that there's serious character assassination happening here, and it's only going to tar the reputation of everyone involved - alleged victims, Appelbaum, and Tor alike. No matter who you're siding with, this is still an ugly and counterproductive episode.