I'll say that I've found a workaround. I used Groups and Scenes and put the fan switches in a scene (actually tried a group first, but it still reported to Google Home as a light, so I had to put them in a scene instead). Now, as a scene, they report to Google as switches, and when I set the name in Google Home to "Fan" or set device type as fan, it even shows a little fan icon, and it works fine for voice and Google Home app control.
However, I would still say that it is incorrect for Hubitat to report the relay of the Zooz Zen30 as a light to Google, it should report it as a switch, then if it is actually a light then a user could manually change the device type in Google Home (presumably, it seems to allow any switch type device to be changed to a light, at least for me so far with some zigbee wall plugs, but if Hubitat reports something as a light, Google wont allow a device type change)
