Great to know, I did not realize there had a keypadless z-wave solution.
Regarding yours, from memory, I recalled there was nothing special about the exterior lock itself. There is a 4-wire you have to pass through to the door for the keypad. But you go with the 910 that is keypadless, I see know reason you cannot just provide your own exterior assembly.
Have you compared the installation manuals to ensure the internal parts are all the same?