I know that's intended as a joke but, for what it's worth, you've given a staged example of a 'known unknown' (that is, a teammate unexpectedly being an idiot).

An 'unknown unknown' is something neither known nor anticipated. For example, if you succeeded in the quest, your real-world bank account would be dinged for $1000, all experience points and loot would be given to a different guild at random and one of the team would be permanently banned from WoW because they were wearing something yellow.