Seem to be missing the key to 1957 room?

Hey all, rounding the bend to the last few major puzzles of the game. I'm at 91.9% Truth revealed, and the only two things I have left in my to-do list is to "help the old lady see" and interacting with the super computer. However, I'm now realizing that I have one puzzle box yet to open - 1957. I've never found the key. I'm pretty sure I need to use the documents found in the puzzle boxes to talk to the old lady, which I will do soon, but just wondering....did I miss the 1957 key somewhere? Thanks