It's an excellent point. If you leave such a gaping weakness in your team, you can't blame the game for taking advantage of it.
Also, his opponent just installed (or reinstalled) the game four weeks ago. Many new players don't fully understand the intricacies of the game during their first couple of months. Since the average rating of level 3 players are around 44, his current level of 49 indicates his team has been trained. It was not an abandoned team.