Not exactly the situation you were talking about, but top set can definitely be behind...
http://twodimes.net/h/?z=636627
pokenum -o 9d 9c as 3s - 6c 7c th jh -- 8c 9h 2c
Omaha Hi: 820 enumerated boards containing 8c 2c 9h
cards win %win lose %lose tie %tie EV
As 3s 9c 9d 330 40.24 490 59.76 0 0.00 0.402
7c 6c Jh Th 490 59.76 330 40.24 0 0.00 0.