Don,
I have seen you on these boards for years and I highly respect your opinions. Let me offer some reasons for my opinion, If you lose your neutral at the service panel, and the supplemental grounding electrode conductor (SGEC)is attached at the meter pan, and the house has a well, with plastic pipe running out to the well. Where is the house grounded wire now? You would have 240 volts into the house with no grounded conductors. IF however the SEGC was attached to the service panel, then you might still be able to have the house function on the SEGC. I always believed that everything should be tied to gether to make up the grounding grid. Anyway you look at it, if the PoCo says no, no matter what I say, they won't hook it up. They don't want anything that isn't under their control in their meter pan.
Harold