I feel terrible having to ask for help, but I’ve been trying to fix this for over a day without making any progress. So if anyone could help I would greatly appreciate it. And if anyone notices anything else I should work on please let me know.
Imagine the engine like a room. Around the room are gas detectors that beep when they detect the prescence of gas (entities detecting a leak). You can use those detectors to find the problem and fix it, or you can do what you just did and remove the detectors.
Ensure the map has a world brush skybox around it. The skybox must not be a func_brush, func_detail, or any other brush entity, it cannot be a displacement, and it cannot be water.