I'm not familiar with their work in general, but there is a reason a lot of these guys go to NXT first.

It's not just that they need the work or to learn WWE's way, but it helps them build an audience, even if a smaller one and a body of work WWE can use to hype them up.

Gallows and Anderson were not popular enough outside of the IWC NJPW fans - I knew of them but don't watch much Indy wrestling so had never really seen them. They came in with such high expectations by WWE but they weren't popular enough to just be popular on their own so it failed.

AJ is really the only "indy" guy that could work for. Omega could do it too- though lots of people still haven't seen him fight.