I am sorting all of my games and found out this has a Multiplayer tag. Is this game Actually Multiplayer? or is steam messing with me?

It's the door to the right of the "Collected Secrets" door. I've 100%ed the game and yet this door still wont unlock. I haven't seen any other people talking about it, so I'm concerned if it's just a me thing?? LMK!!

Soooo, that Duncan radical dude, huh? Ok, I need some help understanding some stuff in the recording. I could understand there was something about "opening a console", but the secondary voice sounded too distorted for me to understand.. anything tbh, so I'm afraid I may have missed some crucial info that is useful outside the trolling that this April fools is (btw, amazing lmfao). Can someone who maybe doesn't have comprehension issues like I do describe what that secondary voice said? Is it anything use...

I was just watching my friend play game and a character said it was a Navigation AI and it was using AI to navigate. AI uses up like 3000 Tons of water per year and causes global warming and Climate Change. I think the photographs were AI too but i can't say which ones becuase its a spoiler...

Does anybody know how to load different maps in unreal engine console commands?