USD character not skinning properly

Hello
I am importing a simple USDSkel animation. I can see my character in Unreal and it has correct textures etc.
But the animation is not working. It looks as though Unreal is not reading the USD skin weights properly.

The usd file views (animates) correctly in USDVIEW, Houdini, Katana etc. But not in Unreal.

I have attached the usd file and also a video of Unreal and USDVIEW side-by-side showing the issue.

I understand you can edit skin weights in Unreal, but I want to be loading in hundreds of animated usds, and dont want to be re-skinning them all

any advice gratefully received

man.usd (1.4 MB)

Any thoughts on this please?