Has NetFree looked into using neural networks to approve pictures?
I am under the impression that yes, they have looked into it and deemed it insufficiently accurate. (They aren't living in a cave and they are aware of recent advances in AI etc.)
If you are confident that your approach can rival the current approach and you are capable of implementing something with those success rates, I would suggest you contact the administration directly. Perhaps the matter would be reconsidered.
(I don't speak on behalf of NetFree, this is my own conjecture)