I must have waited well over 3 days, Still empty casino Any tips?

You might get better help in the New Vegas Spoilers forums, not the ones for Oblivion.

If you get the sheriff ( whoever ) the towns folk will all leave the casino and go home. The casino will empty except for the robot from now on.

The only people who ever go into the casino once you solve Primm's problem are raiders and other ruffians who think Primm is still controlled by the Powder Gangers.

I like ambushing them and stealing their stuffs >:)