[kwwadeace]"I will be using the z1s as their main cameras, and was wondering if anyone now of a way to control the tally light,"
Don't use the "tally" that's ON the camera.
Run another small "speaker cable" connected to a stand-alone indicator light that's mounted very near the camera. Use the tally circuit in the switcher to activate it (might need a wall-wart power supply for that lamp.)
This method could be used for any and all cameras in the set-up, if needed.
That would be an easy workaround that would be a "no-brainer" for a good tech to hook up.