Residing in a headtube doesn't damage a fork's label... but thieves trying to make stolen goods less recognizable does. He says the steerer length is 8 inches, was yours approximately/ longer than that length? If yes, I think you're on to something definitely.

Another note; he sells large lots of parts; check them/ his other auctions for parts that possibly came from your bike if you haven't already.

Did you post a thread on your bike being stolen? (other than this one)