First, I sincerely appreciate this awesome contribution!
I was working on implementing it and discovered that Nest has apparently deprecated the API being used by this Add-On. It's detailed on the Nest Developer's homepage.
https://developers.nest.com/
From my brief reading, current implementations will still work for now, but for a Nest account that has been migrated to Google already, the only option is to utilize a registered app with the new programs as outlined here:
https://developers.google.com/nest/device-access
Nest Error When Clicking the App's OAuth Link during Setup
I attempted to enroll by using my logged-in session to click the OAuth registration link, however I get the below error message when doing so.

First, I sincerely appreciate this awesome contribution!
I was working on implementing it and discovered that Nest has apparently deprecated the API being used by this Add-On. It's detailed on the Nest Developer's homepage.
From my brief reading, current implementations will still work for now, but for a Nest account that has been migrated to Google already, the only option is to utilize a registered app with the new programs as outlined here:
Nest Error When Clicking the App's OAuth Link during Setup
I attempted to enroll by using my logged-in session to click the OAuth registration link, however I get the below error message when doing so.