SkelAnimation and instancing for crowds - what am I doing wrong?

Hi, if any kind soul could tell me what I am doing wrong I would appreciate it. The following ZIP file has a complete set of files: - Google Drive

I am trying to do a variation on what is specified in Universal Scene Description: Instancing in UsdSkel

If you load the “instancing-stage.usda” as is, it will work. The original character (which I would normally make not visible) and all the references to it will play animation clips. But as soon as I turn the instanceable flag on for the original character all animations stop working.

My understanding of instancing is the prim hierarchy under the instanced instance can no longer be updated by overrides, but the root prim property values will work. That is why you can specify some of the properties at the root and let in inherit down the prim hierarchy (the animation clip to use in skel:animationSource). The characters all move to their different positions correctly, its just the animation does not play on any of the models.

Thanks for any advice!