Same controller different rigs

I have several characters with different rig types, one rig type that is humanoid and one rig that is like a horse. I have separate animations for each rig type and have been using an animation override controller to use the same state controller, but different animations per rig. This has worked really well until I needed a layer mask. I created the layer mask, but it only works for the humanoids and not for the horse rigs using the animation override controller. And I can't seem to find a way to change layer masks at runtime. And changing the horse rig to humanoid breaks the animations.

Anyone else have a similar situation that might have a better workflow or setup for this?