Probably was fake, but if it was real, not very smart of him to have it take so long. Should have been an immediate upload so people could download it.
Maybe he was thinking they would leave it up so police could use it as potential evidence.
It would have been a thumbnail of a magnet link to a torrent if anything
I'd be shocked if someone used normal social media to distribute something like that. Meanwhile, drugs and warez and pirated content have developed a well known, well supported, internationally censorship resistant ecosystem.
Maybe he was thinking they would leave it up so police could use it as potential evidence.