I do some photography so I've done some research on legal issues in photography but keep in mind I'm not a lawyer.
I'm pretty sure a contract using only handles and signed using same handles is not enforceable. I can imagine the judge in a contract dispute asking you, "Allright, which one of you is Aether and which one is I Like Big Butts?"
A photographer generally owns the copyright to any photos they take and they generally have the right to post them on their photography website without needing a model release or any further permission from the model.
If they sell a photo without a model release, then they may have a legal problem on their hands.