It is blatant fraud and onlyfans should be suable for this. Fuck that whole company and all their bs pr management workers doing nothing getting rich on regarded male beta simp money.
First you could sue all the singers who have lip synced in a live performance and see how it goes.
But in this case its not OnlyFans doing the (potential?) fraud, it's the individual performers and potentially their agencies. OnlyFans just provide the platform and turn a blind eye.