I am an ASE certified technician working in the automotive service field professionally for 19 years now. I work for a competitor and in my job, we deal almost exclusively with aftermarket aluminum wheels.
I have worked in Texas near the gulf coast, in California (bay area), Oregon, and Washington. I can say with some authority that I have inspected your alleged damage. Some of the smudges that I saw cannot be easily explained by looking at the photos-I have no answer for this.
What I CAN SURELY say is that there is corrosion present on your wheels. Specifically the type of damage around your valve stem hole. This corrosion is something I have seen in Washington state. Specifically, my company had to deal with this exact corrosion on thousands of wheels in Seattle. The damage in question was proven to be caused by a chemical de-icing agent the state of Washington had used the previous winter. The chemical was very harsh and it was not practical (nor expected) that our customers would wash off their wheels after driving in the snow and ice. Some of our customers in the Portland area did see this damage too, and as it turns out almost all of them were making regular drives into Washington.
Being in the industry in as many locations as I have been and with the number of customer service issues I have personally dealt with, I can say that your damage is mostly from corrosion. The mfgr of the wheels you purchased likely did not have the highest quality clear coatings and the coatings that were there were comprimised in some way effectively "holding" corrosives against your wheel. I am willing to bet you are using a commercial wheel cleaner from time to time.
I know for a fact most wheel mfgrs suggest ONLY SOAP AND WATER to clean wheels. I know this may not be what you wanted to hear, but I looked at your evidence, and if it had been my stores on my watch, I would have blown you off too. Dismiss your angst againt NTB and either A) check into what Georgia is using as a de-icing agent on your roads -or- B) quit using chemical wheel cleaners that claim to "break down brake dust". OK there's my $0.02 on your issues. Good luck with whatever happens. -John