Don,
From the original post, I do not interpret the disconnect(s) of the 200A panelboards (load centers ) in the basement as being on the load side of the Service Disconnect.
I do not see the exceptions of 250.142(B) applying to the installation.
The 250.142 in-part states " - - -, a grounded circuit conductor shall not be used for grounding non-current carrying metal parts of equipment on the load side of the service disconnecting means - - -."
Somehow I read your comment to be: "The grounded conductor (neutral) can be used for all required bonding and grounding on the load side of the service disconnect(s)."
In general, once the grounded conductor (neutral) leaves the service disconnect enclosure, the grounded conductor is not to be re-grounded or used as an equipment grounding conductor EGC.
250.142(B) exceptions and 250.32(B).
Maybe I'm missing the meaning of your statement.
