...what really cracks me up, though, is thinking about Kai saying "group hug" in a German accent. 
I don't care who ya are, that's funny right there.
BTW, I'm not saying there's anything wrong with saying "All y'all," I'm just saying it was funny. I usually hear it only when there's an expletive in front of it.
You'ns: (Northwestern PA) You, singular or collective. If singular, refers to you but permits the inclusion of anyone you might know. Slightly different from "Y'all," closer to "Youse."