Maybe see it as a competition of wits.

Yes! Where is the money? A battle of wits has begun! It ends when a box is opened.

Of course, it's so simple. All I have to do is divine from what I know of Omega: is it the sort of agent who would put the money in one box, or both? Now, a clever agent would put little money into only one box, because it would know that only a great fool would not reach for both. I am not a great fool, so I can clearly not take only one box. But Omega must have known I was not a great fool, and would have counted on it, so I can clearly not choose both boxes.

Truly, Omega must admit that I have a dizzying intellect.

On the other hand, perhaps I have confused this with something else.