I don't really understand, the victim of scam knows how to post in Github, probably he had knowledge upon storing Bitcoin in a safe wallet on this community.
I've stored a few thousand on a hot wallet in the past, he could've done the same? Just found his seed words from 2014, put them in and got his wallet back (or just copied the wallet file across).
Won't be the last either, it's similar to the guy who posted the signature to an address containing 1000BTC which climbed to several thousand replies at least in the space of 12 hours.