They were playing a game of Hedbanz / Headbands / Celebrity , and one of them had The Good Witch Glinda from Wizard of Oz as their character, and they are arguing about them not guessing it based on the clues.
Yeah, but I thought he was drawing a parallel between Wizard of Oz and something else, i.e. Elsa is the wicked witch of the East. If it's older than Frozen, then it's probably not that!