When applying directly to BMWFS online (https://www.bmwusa.com/financial-services.html), do they provide a rate on approval or will they just refer you to the dealer for the rate? If they don't provide a rate with the approval, is there a benefit to applying online other than the certainty of approval?
Rates are typically managed/disclosed at the dealer as they tend to mark that up.
The process you're following online is the same process that would occur in the dealership...and some dealers, despite the approval...chose to run your credit again and sometimes offer alternatives to the captive bank.
If it were me, I would just take care of it at the dealership