Board Thread:Questions and Answers/@comment-27973255-20160314015815/@comment-27701762-20160324225410

I believe the Yellow key slot is in the room with the video tapes. To the right of the DT Extraction Machine.

If not, the other two key rooms can be located beyond the yellow flower hallway (go to the room with all of the beds and head right; I believe this is the Blue key slot), and at the end of the hallway with the refrigerators (I believe this is the Green key slot).