I think it might be best for Sally to be killed by a NPC. Otherwise it's gonna be really hard for the captured Lunairans to be accepted by the humans (well, it'll be hard for the ones that choose to join them later on).

...Or she could get killed by Chirok
He's the berserker of the Lunairan platoon, so he's a mindless killing machine.
I could totally see him sneaking deeper into the caves and attacking Sally

Which would you prefer?

Also, I'll try to have my post done today! I'm finally back from my vacation so I have more free time :)