How could possibly this be. While just chatting in facebook messenger and then he did lost his offline wallet. I may be getting the wrong idea but may be he lose his wallet because he let his whoever he whom is conversing with deceive him. It could definitely be a bait link in which your friend find useful. He may be have lack of awareness towards hacking stuff. Because there is no other way around he could protect his wallet other than not letting someone knew his keys. Never ever click a link in which it has something to with his wallet other than the link of the wallet itself, else is a trap.