actually i AM running the bat file; this is what happens, im also using Steamvr, on a quest 3s. (ignore file name i made it quickly to test)
it literally runs it in a normal desktop mode, i have no idea why it doesnt launch properly.
Looks like unreal isn't starting on Stereo mode. this could be that it's just not detecting a headset when starting. Make sure SteamVR is running and the headset/controllers are tracking while starting the program.
If this doesn't work it could be that it's a problem with SteamVR you can try verifying the integrity of SteamVR and reinstalling if that doesn't work either.