Have anyone seen something like this?

Normally I don't call hacks but last game I met a guy who was fishy as fuck (I think he used trigger) They managed to win the game in 4v5 but in the last round, the guy abandoned the game and got a 30 min ban. He left in the last 30 sec so he wouldn't even get a ban if he only disconnects. Have you seen something like this? Is this a way to bypass overwatch or the guy was just stupid as hell?