Good find. While I stand by what I said in the other thread, that the chat logs alone were not enough to conclusively prove a link, this blockchain evidence is irrefutable that these two users are the same person.

It is completely justified for OP to keep the amount he was scammed. What happens with the remainder of the amount is up to him. Personally, I would probably return the remainder of the funds, although I can see the merit behind either donating them or trying to refund other victims of this scammer.