Has anyone contacted Bitstamp about the missing coins?
This is always my issue with exploring into this sort of thing.
Who knows if the original owner even has the coins, most chains have been tainted and even selling the private keys was sometimes done in the past...
I remember nottingham university in the UK had a professor bring out something that blacklisted addresses where "dark funds" ended up (stuff stolen or related to illegal activites) and there is always some dubiousness as most people try to use anonymising services in this space (usually for normal reasons, who wants to advertise how much money they actually have)?