Tracking Cesium3DTilesetGraphics using SampledPositionProperty

According to the Cesium3DTilesetGraphics documentation, the tileset’s modelMatrix is set to the parent entity’s position.

However from my experience this doesn’t seem to be the case - the tileset seems to be in some arbitrary position out in space. I cannot get the exact position of the tileset as a Cesium3DTilesetGraphics does not have many properties to be able to debug.

The Entity Constructor Options documentation states that a tileset can have an Entity as a parent, where the tileset will be represented as an Entity.

My use case is around the tracking of an Cesium3DTileset. Where we would like to visualize the movement of a tileset from one location to another.
From taking a look at the docs & a few sandcastles, using SampledPositionProperty, TimeIntervalCollection, Entity, Cesium3DTilesetGraphics & viewer.trackedEntity seemed like the way to go.

Is this something that is possible with tilesets? This is the kind of functionality we’re looking for, we would just replace the model with a tileset: Cesium Sandcastle.

I have put together a simple sandcastle showing the association of a tileset and an entity. It looks like the modelMatrix isn’t being overwritten by the entity position.

Any info on this?