Unfortunately I can only upload the save file just after Nisbet's death.
So what happened was she was at Fire Pole just about to get Manual Airlock to open but she was knocked out from Heatstroke.
She fell to the bottom of boiling hot water reservoir and stuck doing Climb Pole animation continuously until she died. (see video)
Tried to assign her to TRIAGE COT but still no luck, she's stuck there forever.
After her death, she's still assigned for TRIAGE COT?! (check my save file, bug persist after load game)
Also Nisbet is still assigned in her COT after she died and I have to manually assign somebody else to use her COT or it will stay Nisbet's Cot forever.
Poor Nisbet. only God knows how to set you free from your curse.