Hey, thanks for making this video! I really enjoyed watching it. :)
You pretty much figured everything out.
The mask is more of an extra to make the maze feel more alive, have a bit of a creepy surprise element and to be able to shoot something.
It will just show up in random places and watch you. When shot it will re-materialise somewhere else. At first I wanted it to be able to kill the player and have a whole health and ammo system and whatnot, but since this was done for a game jam in a limited time period I decided to scrap this idea.
I might come back to this project after a while and expand upon it though.
There is one thing you missed. When looking out the window in the room with the checkered floor you can see a whale flying by at times. It doesn't do anything other than being eye candy and an additional hint for the ocean sound though.