I got a splitter in and it works I wanted. It's plugged into the WaterCop and the wired (with lights) auxiliary and the Zooz multi relay are plugged into it.
I can control the valve either way, and the wired switch displays the switch status!
Now, I have to find a use for those 10 z-wave utilitech water sensors, and less probably, for the z-wave WaterCop. 
