I think your argument is logically consistent, and I agree with your analysis of the stomach ache illustration. However, the reason I don't think it's a terribly realistic possibility is that your premise falls foul of Occam's razor. It's very difficult to see why such a hell would be necessary, when oblivion is one of the alternative options. Of course the simplest answer is not always the correct one, but I think then we get into the realms of unknowability again. It may be my limited imagination, but I simply can't see what such an "inevitable consequence" of rejecting the divine would be like, or what sort of metaphysics would require a universe to be set up in that way. It's obvious that free will requires the possibility of "disobedience", but the consequences of such are necessarily mere speculation.