To answer the OP I've had that area apart to put in my XM radio and I doubt a couple quarters could hurt anything. By the way if you have a 2.5/CVT you do not even have gears. Even if you have the 3.6 or manual I don't see how change could enter the tranny that way.
The only issue I could see is it might jam the lever preventing you from shifting. It is very easy to take apart, look up one of the threads for radio install and you should find what you need.