The following method is how to unlock this trophy:
- Examine the lost and found tray in the basement, the tray is on top of the opposite counter from the candles, located in the laundry room, you’ll find a small scrap of paper in the tray, you need to examine the paper to find a partial code on it
- Late in the game, you'll need to open the fuse box which is found in the 5th floor’s janitorial closet. Inside the fuse box door is a stained list of safe codes. Examine the list to find the other half of room 509's safe code
- Finally, put it together and the code is 23-42-16