I have a kit that was half-installed by the previous homeowner, so I finished the installation and linked it to Google Home. The Google Home app displays the cameras as available devices but doesn’t stream video from them. When I select one in the app, Google Home shows me the Device settings screen with this message at the top:
This video stream can’t be viewed here. If you have a smart display or Chromecast, you can ask the Assistant to stream it there.
Assistant does obey voice commands and stream them to my Google TV. I can also use the touch controls on the Home Hub to stream video there, as well as to a Chromecast.