I have Google home set up thoughout my house with about 7 mixed devices, Max, speakers, etc.. I was having all sorts of issues with voice automations so redid some things.. I also set up my mother in law with a google home and with just 2 devices and some lights, drapes, etc... Now, when I switch over to her home on my Pixel, her home shows in "other cast devices", all of my devices?? She is 89, doesn't use the app so not a big deal on that end, does all voice and absoluletly loves it! Her devices don't show up on mine home tho.. any suggestions? don't think it's causing an issue but..
I wonder whether things are just a bit flakey when you have more than one Google Nest "home/structure".
I've noticed that when I'm at my son's house, some of their cameras and Nest Hubs show up in my Google Nest "home/structure" in the Google Home app even though I have no access whatsoever to his household. It seems that, just because I'm accessing my Google Nest "home/structure" while on my son's Wi-Fi network, I can see some of his Google Nest devices. It seems rather buggy and not very secure.
Have you ever tried performing a complete reset on your Google Nest speakers? Let's go ahead and try that and make sure that you will set it up using a new home structure to see if there would be any changes on its behavior.
Keep us posted.