Understandable. Well to summarize it: it was a hidden area, revealing some things about the residents of this enclosure before us. It's open now, if you want to take a look.

That it was discovered, however, was thanks to information gathered on a mission. An MSF Specialist passed on how to find it to one mission-goer as a reward, and I was able to figure out the passcode to open it based on something a comrade and I had seen on the same mission.