Google mesh towers present a problem with the Home Zone box in that they require DHCP to be enabled to allow them to communicate. Any device positioned after the Home Zone box that has DHCP enabled wont be able to register with us properly.
Customer Service Representative
Sorry to hear about the issues you have been experiencing with the Home Zone Box. If it is not too late to return the Google WiFi Mesh, you will be able to extend the Home Zone Box with a standard Netgear WiFi extender (non D-series).
Alternatively, if you have a spare phone line port (pictured below) on the other side of the house, you can plug in a second Home Zone Box which will act as an extender.
To answer your other question, connecting a device that has DHCP enabled after the Home Zone Box is not possible.