It's a very intriguing game with a lot of mysterious things. So many details stood out all the way from the beginning. Like the fact that the way he got there was by falling through a hole that was set up like some kind of trap. Was the whole place built to be some kind of trap? and if not, how were regular visitors meant to enter and why was it built underground, several stories deep judging by how long he fell? There was an opening in the ceiling of the first room specifically for people to fall into this seemingly endless pool, so this place couldn't have been built as a regular pool/spa. At least one of the rooms had balconies, like people were meant to watch whatever would be going on down there
Unless it was meant to be a dream or hallucination; every area seemed familiar yet unsettlingly off in the way dreams often are. And as someone else mentioned, everything was so well-maintained and yet there were no signs of people. The county didn't even know about its existence or authorize any construction, yet there was this monumental underground complex. As the protagonist mentioned, it seemed like it was made to be occupied by a lot of people. But there was nothing about the layout of the pools that would make any sense as a functional waterpark or spa. Or in the layout of the mall
I actually hope none of these things are answered directly, and can instead be theorized about. It would be fun if there are some more hints and mysteries about the lore later in the game