Launch Game does not begin actual gameplay, just a simulation in the level

When I right-click on my uproject and select “Launch Game,” I expect it to actually start the game. But instead, it opens a gameplay window that simulates the environment, without anything actually happening. It’s as if my player controller doesn’t exist – my custom player controller creates a UI and a player character, but none of that gets spawned. I have my custom controller selected under the maps & modes in the Project Settings, and I have verified that it is also selected under the “World Override” settings under the blueprint menu. Any idea why my player controller doesn’t start up in the “Launch Game” option?

BTW, the characters in the level are unanimated and don’t do the things they are supposed to do either. So it’s not just my player controller that isn’t starting properly.