Control Rig - some movement is not captured when baking to anim sequence

I’ve created a simple breathing animation for my character (using character creator 3 skeleton with a control rig I built). The animation is very simple, I move the chest up slightly and the stomach outwards. When I bake to an animation sequence, however, only the arms move (in the control rig animation they move through IK because the chest moves). If I rotate instead of translate, the animation works fine.

Could anyone with more experience in this area offer any insight?