Might look into AlphaOBD.
Not certain if it can help you but pretty sure it can be used to code fob's to the 2015+ cars so it might be able to do it for you as well. Probably needs the full version ($50) plus an OBD2 reader (cost depending on what is required). In the end, might not save you money over the dealership, but if they won't do it for some reason it might help.
Oh, and you still have to buy a fob/key.
