@Spin @femich Thanks both of you for the suggestions.
I contacted customer care again, this time specifying that my original dealership (Dick Hannahs Portland) was marking up above MSRP, and my new desired dealership Herzog-Meier Beaverton explicitly stated they are not marking the ID4 above MSRP. They checked again and were still unable to transfer the dealership. This is absurd to me because it's just a field in a database and has nothing to do with production of the car. Chances are the system simply doesn't let them update the address at this point even though there's no physical reason it couldn't be changed.
I'm not willing to deal with dealership crap, all previous experiences have been bad. So I've canceled the first reservation and made another one for Herzog-Meier. Pushed back the delivery a few months but probably saved me a few grand, so still worth it. Lesson learned!
Thanks again. Hopefully this helps someone else in a similar situation.