By the nature of it being about a BSJ submission I don't think there's any way to be perfectly anonymous. I'd be happy to set up a google form that you could submit image URLs to that only I would see, or give you my FR/discord to do the same, but I can't really think of any way to stay fully and completely anonymous. (I'd also rather not publicly post my discord honestly, though I'd be fine with DMing it through the site or something similar.)

Totally up to you on whether you're comfortable with it; I don't want to force anyone out of their comfort zone.