Sadly Adultwork has no credible competition and I can't see that changing any time soon.
Even if a new player entered the market they would not worry too much about the fakes and scams, they would simply be interested in their bottom line.
That's true. The only credible threat to AW would be a combination of UKE and UKP, where UKE provides the advertising platform and UKP the reviews/feedback including warnings of scams, fakes etc.
It's correct that presently UKE often leads back to AW, but if enough prossies copy across their profiles to UKE (as well as AW), when a critical mass point is reached, AW will start losing ground very fast - mainly because they cannot be trusted.
We all know that well reviewed WGs on UKP do very well indeed, so this can be the carrot for aspiring WGs.
I reckon it can be done, and it will benefit the industry as a whole.