I thought the 10/20 Omaha/8 game at Lucky Chances was Thursdays. The Tuesday game was the short-lived return of pot-limit.
(I checked my journal and I'm sure it was Thursdays in the past... but last time I showed up on Thursday it wasn't running.)
I haven't seen an Omaha game run at Garden City except for the day of their Omaha tournament last May; certainly not at 6/12.
Bay 101 4/8 Omaha may not be all that live. Artichoke Joe's gets a table or two running on Wednesdays from people leaving the 1/2 Hold'em 1/2 Omaha tournament, but I think not other days of the week. (
http://poker.wikia.com/wiki/Artichoke_Joe%27s says only Wednesday and Friday.)