How do I get Cesium3DTilesets for child elements?

If I include several other Tilesets as children via a root tileset.json, which are assigned to different boundingVolumes, I only get the root tileset via viewer.scene.primitives. In the PrimitiveCollection I can then get to the children via root.children, but there they are only available as Cesium3DTile.
Is there any way to also get to the Cesium3DTileset of the respective child element? There is information in the tileset.json files that I need to read at runtime. This is possible from the root tileset, but not from the children.

Hi there,

Cesium3DTile objects have a tileset property which should contain a reference to the original 3D tileset.