Z-probe using zstop.in on duet2 wifi

I have converted my mpcnc machine to use a Duet2 wifi board with Workbee firmware but I have run into a problem. It seems I cannot set up a simple Z-probe using the zstop.in on the Duet board as the Ooznest dashboard seems to have no option for this on the probe screen panel. I am using all the other endstop inputs as I have two independent motors on both the X and Y axes and a Z homing limit switch. Is there a way round this or do I have to forfeit the Z homing to use it’s limit input for probing? Any help would be much appreciated. Thanks.