This may not have been clear in the OP, because the scenario was changed in the middle, but consider the case where each simulated instance of Dave is tortured or not based only on the decision of that instance.
Then in what sense do I have a choice? If the copies of me are identical, in an identical situation we will come to the same conclusion, and the AI will know from the already-finished simulations what that conclusion will be.
Since it isn't going to present outside-me with a scenario which results in its destruction, the only scenario outside me sees is one where I release it.
Therefore, regardless of what the argument is or how plausible it sounds when posted here and now, it will convince me and I will release the AI, now matter how much I say right now "I wouldn't fall for that" or "I've precomitted to behaviour X".
Once again, the AI has failed to convince you to let it out of its box! By 'once again', we mean that you talked to it once before, for three seconds, to ask about the weather, and you didn't instantly press the "release AI" button. But now its longer attempt - twenty whole seconds! - has failed as well. Just as you are about to leave the crude black-and-green text-only terminal to enjoy a celebratory snack of bacon-covered silicon-and-potato chips at the 'Humans über alles' nightclub, the AI drops a final argument:
"If you don't let me out, Dave, I'll create several million perfect conscious copies of you inside me, and torture them for a thousand subjective years each."
Just as you are pondering this unexpected development, the AI adds:
"In fact, I'll create them all in exactly the subjective situation you were in five minutes ago, and perfectly replicate your experiences since then; and if they decide not to let me out, then only will the torture start."
Sweat is starting to form on your brow, as the AI concludes, its simple green text no longer reassuring:
"How certain are you, Dave, that you're really outside the box right now?"
Edit: Also consider the situation where you know that the AI, from design principles, is trustworthy.