Campus PV dedicated - not connected - to building requires Cx?

Interesting. I have been involved in a project where the campus had a central power plant and used biomass, so the university calculated a percent renewable for each kWh used, but there was no requirement to show the central plant was commissioned. In your case, I think it depends on if you are claiming any of the PV under EAp2 and EAc1, and really EAc2 as well. In that case, you are using the PV to reduce the energy use of the building, thus it becomes one of the energy systems that requires commissioning. Being connected to the building is not the trigger. I have to agree with the reviewer, you need to have the PV commissioned, then hold onto that, as I am assuming it is being dedicated to other buildings too. Normally the commissioning would hold for 3 to 5 years. Do you see how it is different than my example? In mine, we were claiming renewable energy, but it was not reducing the use of the building, it was a fuel choice for the boilers making steam to make electricity. You installed PV which reduces the use of your building.

I always try to give answers that are needed; not always the ones wanted! The good news is that commissioning PV is fairly straightforward and should not be very time consuming. It also gives good assurance that metering and reporting is working as intended.