The event where you have to kill the guards around 3 sitting prisoners and have done so, occasionally bugs and wont give me a prompt to untie them: can still get a prompt to feed my pet as norm and possibly "pet" my badger(lol!) but no untie option prompt for prisoners. The only way around it i've found is walking a distance from the event spot(50+ so far) after making sure they are safe and getting the prompt icon up in the upper left hand corner of the screen to save them all over again,