The user is trying to load an addressable prefab that references non-addressable animator controller. The controller reference will need to be replaced at at runtime.

If the controller is addressable (loaded from an asset bundle), it also needs to be rebound to the rig system.
This can be done by:
animator.enabled = false;
animator.runtimeAnimatorController = newController;
rigBuilder.Build();
animator.enabled = true;

However the prefab will not be animated as expected. The prefab's MultiPositionConstraint weight parameter is animated, but its source object weights remain unbound.

How to reproduce:
1. Download & open the project from the google drive link
2. Open the SampleScene Scene
3. Open the Addressables Groups window (Window -> Asset Management -> Addressables -> Groups)
4. Set the "Play Mode Script" to use "Use Existing Build..."
5. Delete the existing asset bundles (Addressables Groups window -> Build -> Clean Build -> All)
6. Build the asset bundles (Addressables Groups window -> Build -> New Build -> Default Build Script)
5. Enter the Play Mode and observe the Game view
6. See that the cube isn't being animated, but its MultiPositionConstraint (attached to this GameObject in the Hierarchy view: RootAddressable(Clone) -> Rig 1 -> Interpolate) is applying different weight values on its Source Objects.

Expected results: The cube is animated (moves left to right)
Actual results: The cube isn't moving.

Reproducible with: Animation Rigging 1.0.3, Addressables 1.17.17 (2021.1f1)