My description was a little unclear as I was calmly panicking.
Ok, that was disappointing, I thought you just discovered a new bug.
I am 95% sure that is the correct situation, but I have a nagging question about why I can not see that "Change Address" from within the Trezor, even if I do an export to a CSV.
Well, it's probably because they want to keep the GUI as clean and neat as possible, and that makes sense, it's like checking your hard drive space, it won't bother you with all the details, it would just sum everything up and tell you that you got x filled and y empty, if you need more details -- you going to have to dig further.
If you still want to see your change addresses you are going to need to use another wallet or use coin control which is easier, just do as if you were going to send some
BTC, and you get that setting icon that allows you to use coin control, that would display a breakdown of your balance, this address holds x BTC and that address holds y BTC, it's been a while since I used Trezor but ya I am sure that would work.