bisker's Comments

SPOILER: If you can't leave office like me (see Midlifecrisi's comment) then you probably missed the grate - to the left of the chair, on the wall.

The green key chest has a glitch - if you went to the Camp 5 dungeon and had full inventory when opened the chest, you will not pick up the key and the next time you come back, the chest is open and empty leaving you forever without the key.