The short papers accompanying the submissions are not out yet, but apparently the winning team did not use ML at all:<p><a href="https://mobile.twitter.com/alexkontorovich/status/1423259110817112070" rel="nofollow">https://mobile.twitter.com/alexkontorovich/status/1423259110...</a>
General introduction to the TSP problem video by a member of the winning team:<p><a href="https://m.youtube.com/watch?v=vQMFVLa7yYQ" rel="nofollow">https://m.youtube.com/watch?v=vQMFVLa7yYQ</a>