what is stopping AW from doing this automatically themselves before new profiles are allowed to be active, at least for the main photos on a profile, after all if there are some in a gallery of somebody different that should be fairly obvious. Similarly if photos are changed, only show them after they have been checked (which in most cases with real photos is likely to be instantaneous).
From experience of finding copied photos, it isn't always an instantaneous process. Thinking it looks fake and finding the matching image isn't always straight forward. Automated searches aren't conclusive.
The solution to a complex problem isn't usually one thing so there are probably a bunch of counter measures needed.
Maybe AW could ask profiles to reverify when they make large scale changes to their profiles ? that could be data driven and automated to keep the costs down.
I'd ask AW to bring in a bounty for every proven fake reported but that would just get abused. Pity, because if I had a credit for every fake I'd reported I'd be able to buy someone nice something good from their wishlist