USD collision in 5.4

I saw this demo using USD from blender. The workflow seems perfect, except when I add a simple box collision to the floor mesh, the player just goes right through it. Unchecking ‘Never Need Cook Collision Data’, but that didnt’ solve the issue. I was curious if the mesh simply wasn’t saving, but when I return to the mesh editor, the box collider is there. I even changed the material color to ensure that changes were persisting, so it isn’t like the USD stage is overriding changes.

I am stumped. I was really hoping to use the USD reload so I don’t have to rebuild every scene/level in Unreal.