Keep in mind that round 2 counts twice as much as round 1, so anybody that advances still has a shot at first place. Of course, it's a lot harder to have consistent success with all six teams in round 2, playing against 23 other very good players.
It's sort of the like playing in the World Series of Poker Main Event. In day 1, you face a mixture of professionals, good players, mediocre players and poor players. But as you get deeper into the tournament, almost all the players are very good or better.