An alternate conclusion might be to employ a third party firm. Actually two or more third party firms. There'd be some overlap and a majority vote among the overlap for strongly Approved / Rejected ads.

Crucially the rate of pay would be based on a given provider's quality for the over-reviewed test cases.

Also every provider would verify with "moron in a hurry" standard of confusion / disinformation. They might also flag questionable items for review by regulatory bodies in cases where it isn't clear.