Hmm... I'm unsure of this Alistar pick versus SKT's comp.
Edit: On second thought, MSF does have Cho/Sej. Everything is pretty much loaded into their Sivir. Sivir better be able to handle Ryze/J4 jumping on top.
Game was more or less over after the failed T3 dive. Misfits teamfighting was extremely weak and was largely reliant on bursting down one target and winning the 5v4 and once it got to the point where Cho, Sej, and Karma damage isn't too threatening they couldn't pick fair fights anymore since Sivir's DPS pales in comparison to Trist and she had Ryze backing her up for DPS. At that point SKT just needs to 5 man and since Misfits' split push potential was not very good it was hard for Misfits to try and force them to do anything else.
Trundle was the only character exposing himself and the only thing that Misfit's team can do is try to burst down one person. The game was only going to get worse for them as the game went on and SKT's tanks got even harder to kill so their options were limited.