I've just tried to get the watch and earn mission. Clicking on the provided link leads me to the LPL stream (which is not even live right now); manually chaning to LCK shows "GRF VS KT - GAME 2" as the current game, although that game is long over. After watching the entire HLE vs KZ Game 1 I did not get any progress (I have not watched Grf vs Kt Game 2 at all and don't have any mission progress. So it's not like the system is thinking that I have already watched a game since the stream apparently thinks it's still Grf vs kt game 2).
Every week we get a new watch and earn mission. And so far, every single week it's been bugged :(