He Doesn't Know / He Knows
When Joe tries to predict something in the plot of the game he's playing, people in chat who've played it before tend to say "He doesn't know", followed by the Twitch emote LUL, when he gets something wrong. There are more variations, like "He lacks critical information LUL", and "He hasn't played this game before LUL". Most notably, however, is "He is not cogniferous", followed by the emote jphCoggers. There's also the opposite variant, "He knows LUL", for when he correctly predicts something. Alternatively, chatters sometimes simply say the Twitch :) emote, to mean either "He doesn't know" or "He knows", without revealing which.