Morph Targets for ARKit acting strange

I created the Apple ARKit 52 Blendshapes on a custom character in Blender. It all works well there. When I import the FBX, it comes with all the Morph Targets, but there is one peculiar problem: the eyebrow in browOuterUpLeft movement is activated with every morph target! That mean MouthOpen also gets browOuterUpLeft, and same with the others. And the browOuterUpLeft morph target itself doesn’t move the eyebrow (although it does move the skin underneath). I imported twice with minor random changes to no avail. Does anyone have any experience trouble shooting imported morph targets?