I finally found another disc. However, this one was found in the writer's room. Next to the disc were some old documents from the Marketing Department, wanting this DLC to include more than 1 story! The Writers must have been in a tizzy afterwards, because there were also piles of resignation letters, some with certain words towards marketing. One other strange thing to note, the disc was stained with old blood, spelling out "save us". I don't know what kind of hell happened in this room, but whatever it was, it seems to be something I need to have a further look into.