I am assuming the finance manager have not even submitted the paper work to the BMW extended warranty department yet, I would not play hard ball just yet. Like many have said, I would talk to the sales manager and ask for a apology from the finanace guy for been rude. Just remember, the power is in your hands since you have not fill out the survey yet.
This story is so familar to me, I dont know how many time I had good experiences at a car dealer right up until I meet with the finanace manager. Must all those guys be jerks, is that a job requirement? I have met a few nice finance guys before, but they are very few and far in between.