"Show Loading Movie" not working for VR Splash Screen

I’m using Splash Screens to create a loading screen for my VR game (https://docs.unrealengine.com/en-us/Platforms/VR/SplashScreens).

I got it working with a simple, still texture but I would really like to use an animation. There’s an option in the “Set Splash Screen” node called “Show Loading Movie” and I assumed I would simply need to check that box and add the animation as an mp4 into Startup Movies in Project Settings.

Unfortunately that doesn’t seem to work and I can’t find any information about this anywhere.

This is what I have set up in the MotionControllerPawn.

I’ve tried it with and without “Show on Set” checked, and both with and without a Texture connected.

I used the example video provided in the second comment in this thread.

Any ideas?

4.21.2 nothing has changed. Still not working. I tried media textures as well - no luck.