You should be able to add a 2nd property to your Google Home app by clicking the “+” icon on the top left in the app. Then when you have created a 2nd “home” you can add new devices by clicking that same “+” icon when you are in the screen for the 2nd “home”. Shouldn’t have any issue adding just the Google (non-learning) therm. I believe you could even add a non-Google branded therm but you’d have to select “works with Google” in the “Set up a device” screen. Hope this helps!
Thanks for your answer, Earl_B — this is much appreciated.
BarryPoz, chiming in to ensure you've got the answer you're looking for. You may also check this link to know more information about managing homes and products in your Nest app: https://bit.ly/38rtzDT
Hope this helps.