@BGbreeder - The installer admitted to misunderstanding Tesla guidance and that they should have used 5kW per PW2, that's why they comp'd one. The panels being pole-mounted is irrelevant. Any inverter(s) capable of producing > 5kW per PW2 is likely to cause the GW to shut down the system during peak production which is what we saw happening. Cloud edge effect may be enough to cause it to happen even with less than ideal slopes. At least that's my understanding after having spent way more time on the issue than I wanted
What @BGbreeder is saying (which I also agree with), is that it is "Likely" that Teslas guidance on "7.6kW PV per powerwall" is a catch all recommendation because in general someone with 7.6kW of RATED solar is probably not generating more than 5kW of power for any length of time.
This would be due to the fact that Tesla itself does not do ground mounted solar, and their guidance is based on multiple roof planes, imperfect roof angles etc, not a ground mounted system that can be all faced in the best direction, at the optimal angle for the location.
Its my belief that your installer likely did not account for the fact that Teslas guidance includes they dont do ground mount systems, etc, and they (your installer) provided you incorrect guidance because of it, and decided to do the right thing and take care of you as a valued customer.