Sucky situation, but it happens sometimes. Probably see that exact scenario a couple times a month here, as you can imagine there is a few flaws in the logistics. A sales guy at the selling dealer could be in the midst of selling the vehicle as you are buying it elsewhere, and it hasn't been updated in their locate system yet. Or it is a demo, or a loaner etc etc. Obviously a random dealer that is giving up a piece of inventory to another dealer for no net profit is going to be inclined to look after the guy sitting in front of him, not another dealers customer.
Just be reasonable with the dealer and I am sure you aren't locked into anything. However, just see if they can locate you something that matches what you are looking for in a reasonable time frame. If you are satisfied with the dealer thus far, an honest mistake should not be a deal breaker.
That, or come get the CP deal on a vastly superior VW Tiguan
