Can you have neutrals on ground bar only bonded through main panel body
It may sound funny but it is ok and even required in a way your neutral and ground being on the same bar is fine but look closer and you will see a jumper to ground (the panel is required to be grounded, your grounded and grounding conductors are tied together and then to the case so it is functionally the same on separate bars that are bonded and connected to the case.