I'd imagine C9 don't really care about the result of the tournament as much as they do getting a tested roster for OWL. They spent $20 million on buying in, so the $100,000 prize pool is barely worth bothering with on the large scale. With so many free agents out there, and only single-week roster locks, it makes sense to swap players in and out each week to see who has natural synergy.
I'd like to see them try some UK players though, seeing as they'll be representing London, but it's hard to make strong arguments for who they'd pick (MikeyA vs Sinatraa, ChrisTFer or Numlocked vs Mowzasa, etc. ) Kyb is still part of C9 I believe, but not on the roster this week, but that doesn't mean he won't be in the future, unless I missed an announcement.