After hearing the conversation between Ricky and Ted, Ted will go downstairs with the guard and the money. You can either go downstairs too or speak to Ricky (it will send you to a prison, but you'll get out and the result is the same).
Then, you'll appear right on front of the elevators. Wait for the animation to end and go to speak to Ted. He'll tell you that it was nothing personal and that he'd like to finish this thing with a competition of stealing.
You must refuse this competition, then go to the right side of the casino and steal the normal bag, right where there's a barman. Then go where Ted and the guard are and "steal" again to change the bags.