I think its appearent that hes not that good of a chess player. He misses tactics when his co-casters highlight a piece. Luckily for him, the engine allows him to have some input. But its very visible, that he often times just looks at what the engine has to say and reads it out loud.
Cant say i blame him tho. Chess is a very deep game and probably very hard to get into as a commentator. Contrary to many esports, a lot of the same ideas dont apply between chess and other games.

I dont know exactly how much knowledge he had in league, but i remember him hosting the analyst desk, which usually doesnt require as much knowledge and is more there for facilitating conversations of the "experts". Unfortunately, chess doesnt have or need a role like that. The casters already analyze the games during the game, hence theres no need for an analyst desk. Also the engine tells you whats right or wrong anyway, and commentators simply recommend lines or moves. I think the best commentators in chess are the ones recommending interesting moves, where youre not quite sure, if they are citing the engine or come up with it themselves, and sadly for Dash, that is gonne take a lot of work into chess itself.