The current Asc3's are literally Immo3 every other act, and high Immo3 at that, they're still playing in high Immo lobbies consistently, Asc3 for someone in that high MMR bracket is meaningless.
He is smurfing in radiant and before someone say he is playing vs low immortals go check other top players on the leaderboard all of them have enemies that are low imo so its out of his control (playing duo)