I'm the same anon who posted this >>32556 and I kept investigating on it in my free time as a personal challenge, because I don't really care about marky.
It took me little time to find out that that type of filename is obviously following a pattern ( 7 characters with mixed uppercase and lowercase letters) and that it's from a social media (imgur), as I predicted previously.
Random examples:
https://i.imgur.com/PcTJmXO.jpg
https://i.imgur.com/pnTLoaW.jpg
https://i.imgur.com/cWTrEfP.jpg
https://i.imgur.com/PntvNnz.jpg

Ergo the source is https://imgur.io/MpHpIYJ.jpg which redirects to https://i.imgur.com/removed.png because NSFW content was banned from imgur in 2023, but the link was working before than that.
Do whatever you want with this piece of knowledge.
Case closed.