I just saw a thread requesting other posters judge OP's age/weight/height using a photo. Some posters even include their face.
Usually on threads like that, some of the comments are harsh and uncalled for, and there's no way of knowing if OP is actually the person in the photo, or an abusive person trying to hurt someone else by uploading a photo of them for public scrutiny.
On Reddit posts like this, users are required to either message mods with proof that it's them in the photo, or be holding up a piece of paper with the name of the subreddit written on it in the photo they post.
Would something like that work here? Perhaps either requiring the username in the photo posted, or having a mod check that a photo with the username in matches the person in the photo that OP would like to post.