I can't speak about other managers but the campaign I manage, AI contents are not paid for, we manually go through every posts before payment. You can always tag campaign managers to your report or send a PM.
Yes, if there is a problem or if the AI post or any scam is involved, then the manager of that campaign can be informed if the user is participating in a campaign. But the managers of all the campaigns running in this forum are very good, they look at the posts and then count them. Still, if they have any mistake, they can be informed through PM. Moreover, no campaign manager pays for any AI post.
If you see an AI post and report it, it will be deleted if known that the person used AI to construct his post. This is what I have noticed about the use of AI on this forum. So it is very likely that the campaign manager will not even see the AI posts from who we believed is a good member.
About campaign managers counting post, I will still think that they will likely find it difficult if a gooy members used AI, unless such member are reported like how they are reported on this thread.