After the group draws I can see a world where H2K wins it, but I don't think it's likely.
H2K would match up pretty well VS SKT, their mids and bots are fairly comparable and Odo is less of a weakpoint than Bengi/Blank. I think I'd give H2K about a 35/65 chance VS SKT. Of course the problem with this is it assumes SKT will beat Rox and H2K will beat SSG. I don't know how SSG VS H2K would go, I'm pretty sure that both of these teams will beat ANL and C9 but I have no idea how they'd match up. SKT VS Rox is easier to call, Rox have an advantage, but not a huge one. SKT has been Rox's kryptonite for a very long time, I think they're the only team at worlds who can stop them.
I really wouldn't give C9, ANL, EDG or RNG credit to move past quarters though. I think they're all significantly weaker than the team they're playing against. ANL could surprise but I'm doubtful about their ability in a Bo5, I think that they'd get found out pretty hard after 1 or 2 games.