Why can't you be the trusted party? At the end of the day, one of your servers is involved in the blockchain and using server capacity to do that. Why can't you just use that server capacity to host a simple app where people send the images?

I think if saying that it’s a simpler, easier solution that provides the guarantees that you need, and the other poster still does not understand this, it’s safe to say you shouldn’t put more effort into this. Thanks for your explanations :)