Ah, I see. You're saying Omega must prove to you that your prior made Upsilon less likely than Omega all along. (By the way, this is an interesting way to look at modal logic, I wonder if it's published anywhere.) This is a very tall order for Omega, but it does make the two scenarios logically inconsistent. Unless they involve "deception" - e.g. Omega tweaking the mind of counterfactual-you to believe a false proof. I wonder if the problem still makes sense if this is allowed.