Scott decides to respond with a barrage of photon torpedoes
I disagree with this characterization. Scotty's line is, "We can't fire full phasers with our screens up, and We can't lower our screens with their disruptors on us. Of course I could treat them to a few dozen photon torpedoes." From the tone and delivery I took it as an expression of frustration rather than a serious idea he had, let alone one he had already decided on.
General Order 24: An order to destroy all life on an entire planet.
Which is a really weird thing for Starfleet to have a protocol for. It makes more sense if we assume that GO24 is actually some kind of quarantine/sterilization procedure intended to prevent the spread of dangerous life forms.
Kirk hails the Enterprise informing them to standby to transport the party in ten minutes or carry out General Order 24 on schedule.
If he was bluffing in the first place then he would still be bluffing here. There would be no point in tipping his hand until the situation was under control, which at that point it was not.


