You're asking for a character analysis on a guy we don't know. Impossible question to answer.

The closest I can tell you is this: I've seen good, honest guys do stupid stuff they probably regretted afterwards whenever the "environment" was badly encouraging them. In my case: put 20 soccer guys into a dressing room and once those kinds of talks start flowing with some beers, some things shouldn't be shared (just shown, or thrown in a whatsapp group chat).

So yes, it is possible he will share it to brag or have his "moment de gloire", even though that could be out of character.

It's also possible he's a decent guy who will lock this in his phone until he's bored of it and deletes it some months later.

You never know.