Object Ids with material type not working properly

Hi guys, I’m currently trying to use object IDs for a render, but with the material type.
According to the documentation, it should group material instances with their parents in one layer, but right now it doesn’t. Cinematic Render Passes in Unreal Engine | Unreal Engine 5.6 Documentation | Epic Developer Community

Is anyone else experiencing the same issue? Just wanted to clarify before submitting a bug report.

Here all the materials are child of the NewMaterial black

And here i still have 4 layers, one for every material instances