How come it says 3 points under prize distribution for 4th place spot in playoffs?

Mibr, Cloud9, and Nrg all currently sit at 9 champs points each. Once you reach top 4 in playoffs you get 3 extra points for 4th place and 4 extra points for 3rd place. Why is it that Mibr already qualified even though C9 and Nrg will both pass them in champs points by their next match? Can someone please explain this to me.