I think this is the confusion, I believe Jim is saying the neutrals need to land on a bus that is directly connected to the grounded service conductor. The neutrals cannot land on an aux bus that would require neutral current to travel on the enclosure to reach the grounded service conductor.
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Correct Ryan.
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Thanks, Ryan…that was the confusion from my perspective.
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Yes that is what Jim stated. If you bond an EGC bus directly to the enclosure and then land a neutral(s) on it the neutral current has to travel through the enclosure metal, through the MBJ (green screw or strap) and then back on the neutral. That is in direct conflict with 200.2(B). Some have argued that if you added a wire jumper to the EGC bus is would satisfy 200.2(B) which according to the wording of 200.2(B) it would however you would still violate 250.6 by directing objectionable current through the enclosure. Even if a wire jumper were installed some of the neutral current would still travel on the parallel path of the enclosure.
200.2(B) Continuity.
The continuity of a grounded conductor shall not depend on a connection to a metallic enclosure, raceway, or cable armor.
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You contradicted yourself. It can’t be both isolated and bonded. If they were isolated (which I am certain they are not), you would have a big problem.