After baking my lighting, one object becomes dark:
Freeing the bake causes it to return to normal:
It is not a problem with the material, since the walls and floor are using the same material. The character mesh below the dark mesh is one I have made myself, so I don’t think it is a problem with my Blender to UE4 workflow, although the successful mesh is skeletal, so it might be different.
EDIT: The mesh now shows strange z-fighting type glitches. I have checked, there is only one instance of the mesh, the mesh only has one copy of each face, and double-sided geometry is not enabled. An example is shown here:
