[...]unless we know who you're talking about we won't be much help
I agree with emirlidan. You may have misunderstood some information that you saw. I would assume that a pro with any sort of notoriety wouldn't risk their poker career by accessing a
poker site by illegal means, and there is no pro or poker site that is above the law. The restricted sites aren't allowed to operate in restricted areas, regardless of whether a person "places good", "puts a lot on", "gets certain attention", or any other form of prestige. If you see a pro playing on a restricted site, then they are in a legal State, or they are in a different country. Otherwise, they could be utilizing some IP address wizardry to fake their location. I'm not sure if that is illegal, in itself, but doing it to play poker in an unregulated State definitely is.