They can't meet because they are on the same side of the brackets:
http://www.worldgolfchampionships.com/scoring/r470 The final is the left side vs. the right side. Just the way it is set up. Typical - Phil moved into Ernie's spot, therefor 2 vs 3 and on the other side Goosen moves to 4, so Singh vs Goosen (1 vs. 4) if all the match winners went according to ranking. It sets up for a possible 1 vs. 2 in the final. It's just the way pools are made.