Meerkat demo, groom not rendering on stencil layer

Hi, I’m using the beautiful Meerkat demo project to test the renders. In my project settings, the alpha is enabled. In the plugins, the groom is enabled. In the Movie Render Queue, I use the Weta preset MoviePipelineConfig_Temporal, the provided map and master sequencer. The final EXR render looks good. But when I am trying to render a separate layer of the meerkat (stencil) with an alpha, the groom doesn’t render, he looks like a rat.
Any help is appreciated, thank you!