[WetBeaverNeeded]

I'm pretty sure it's a glitch, it's happened to me as well and the other guy was none too pleased about having to use my team so he went ahead and quit. He was used to his superteam and felt the need to send me a message calling me all kinds of expletives.

Based on that i think it's safe to assume he didn't perform any malevolent actions to cause this scenario.