I would say not likely....When battery dies you will get funny symptoms, but not typically the ones you describe. You should check battery voltage (parked and running), which you can do with cluster sub-menu (look it up)

Who did the steering angle and yaw sensor? I think one and possibly both have to be reset with INPA or some other computer tool after replacement.

was the idle speed error the only error code you got (other than the lights and failsafe mode message)? I guess I would drive it and see which codes come next.