Yes, I think he is legit. It's backed up by Sara Carter https://saraacarter.com/russia-probe-twist-a-billion-dollar-ceo-a-convicted-russian-agent-and-the-fbi/ it's consistent with the interviews he's given on television programs over the years (even going back to 2006 and the SEC probe, which you can look up on YouTube).

Even Warren Buffett vouches for him: https://www.rollingstone.com/politics/politics-features/maria-butina-russia-spy-fbi-860256/

And yes, it does read like fiction but I believe it is the truth.

There are good people there are bad people and there are neutral people in the bureaucracy who just try to get along.

The deep state has had bad people in the highest echelons for too long. That has to change for things to change.