Sneaky Insurance Trick #1: "Yeah, we cover GRS!" Translation: "Yeah, we cover GRS but we really don't want to because it's still such a hot potato, so we give you the option of the weirdest surgeon we can find and hope that 99% of you will say 'screw that, I'm going to pay out of pocket for someone far better.'"
And it raises the question, is free with an unknown surgeon better than nothing at all?
But we're talking about the US here; having a butcher for a surgeon is unlikely. I'm sure he's at least able to offer average results or he'd have lawsuits coming out of his ass by now. And if he's your only option, then I'd probably advise going for it if your financial situation is highly unlikely to change in the future. I mean, what other options are there?
But to answer your question, in all my time spent researching pretty much every US-based surgeon who is even vaguely involved in GRS, his name has never once crossed my radar.
I'd move forward with him, and I'm sure that he'll be able to tell you about what he's capable of doing, how many surgeries he's performed, maybe show you some photos of his work, etc. He might be one of those surgeons who doesn't make a huge song and dance about their work with the transgender community - they do exist (although that in and of itself raises new questions about why it's being kept a secret part of his practice: worried about scaring off non-trans clients and losing income as a result?)
Hopefully a consultation with him will lower the red flags, because free surgery is huge!