pixel_player15678040
First, talk with the guy at the entry to the level/area, then go talk to each person in order EXCEPT after the guy in room one (with the stool & stove) says he can't help? Clear behind him and open the chest, if he still says he can't help go back to entry talk to the guard, then go back to room one and talk to him again. Then the rest of the room in order, using this as the identifier for the rooms:
Left side, top to bottom 8, 3, 6
Right side, top to bottom: 1, 5, 2, 4
Entry, bottom: 7