Didn't Fnatic get all-killed by Zenio? (that may have been Dignitas, forgive me if I'm wrong). If so they may have more depth than Mouz but not necessarily more skill when you consider Mana and Hasu, both capable of beating top Koreans on their day. Zenio isn't the best player so getting all-killed by him is like EG getting all killed by Monster - a good Korean Zerg, sure, but not one that should be all-killing.
Anway, SlayerS first for sure but 2nd and 3rd could go either way if Mana and Hasuobs show up.