I am unable to migrate my nest account to a google account. each time I try to complete the migration, it tells me "oops! We encountered an error. Please try again." with no other context to what the error could be. I am unable to use my Google Hub camera without this migration happening and I have no clue how to fix it. 90 mins chatting with Google support was zero help. hoping someone else had this issue and can help!
Sorry to hear about the issues that you're having with migrating your account, I'm sure it's frustrating but I'm happy to help.
I would suggest reviewing this article first to see if it answers your questions. You may want to also double check that you're using a personal gmail account instead of a Gsuite account or Google Workplaces account.
Please let me know if you have any other questions.