Matthew Mercer has become one of the big TTRPG Dungeon Masters. He’s run games for Vin Diesel, Stephen Colbert and other celebrities such as Terry Crews through the CelebriD&D series.
Critical Role is most likely where you know Laura Bailey from. Unless, of course, you enjoy reading video game and anime credits.
Liam O’Brien could appear (sort of) in a variety of places. When you really look into it though, he is everywhere, he is behind an entire army of voices.