The recently closed Shadowdark game jam had a similar disclosure requirement. If you’d like to see what those disclosures looked like, I think you can still download many of the entries for free.
I believe 3 of the top 5 used AI art. Only one of the top 5 used AI art. But you can peruse many of the entries to see how they disclosed their use of AI art.
I’m also not a fan of AI art but the cats out of the bag and even if people were told they couldn’t, there’d be a good chance people still would and would have some plausible deniability.
The stuff done by humans is way more consistent in style though, and if you are an artist I look forward to seeing what y’all make.
I’m debating on doing this jam as well, but probably just won’t have any original art as I have no skills in that department. The best I can do is hack together public domain art in an image editor and apply filters to it :’)