There are really two issues here (1) the mistake and (2) the finance guy's attitude.
I like dunderhi's suggestion of escalating the issue to the owner/manager and demanding an apology. You're not going to change finance guy; he'll still be the scum of the earth (along with most other car dealer finance guys), but he will at least feel like a jackass for a few minutes.
Customers should not be treated the way he treated you. It's very true (as someone pointed out) that if he discovered an error in the dealership's favor, you can pretty much guarantee he wouldn't call you up and apologize.
Another option is to tell them you will be honest about your poor experience on the BMW survey where they beg you to give them an A+ across the board.
Then tell them you recognize it was a mistake and are happy to have the documents updated. Who knows, with a few survey threats, they might just leave it at 100K if you'll give them all "10s."
2008 535xi 6-speed
- Blk Sapphire, ---2011 535xi
- Jet Blk, Blk Dakota,
Blk Dakota, Bamboo Prem | Cold Wthr --
Aluminum | Prem | Prem 2 | Cold Wthr
Sport | iPod/USB | Nav | Sat --- -------
Sport | Sport Auto | Fold Down Seats
Fold Down Seats | Htd Rear Seats -- ---
PDC | 18" wheels | Logic7