From a game-theoretic standpoint, an AI has a massive benefit if it can prove that it is willing to follow through on threats. How sure are you that the AI can't convincingly commit to torturing a simulation?
An AI in a box has no actual power over the Gatekeeper. Maybe I'm missing something, but it seems to me that threatening to torture simulations is akin to a prisoner threatening to imagine a guard being tortured.
Even granting this as a grave threat, my next issue is that overtly evil behavior would appear more likely to lead to the AI's destruction than its release. Threats are tricky business when the balance of power favors the other side.
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.