Not sure if Gold Auto renewal is off?

Your best bet would be to contact support directly so you can speak to billing to make sure it's turned off. If it's not, they would be the ones to make sure it gets turned off.
support.xbox.com/contact-us

When you turn off the auto renewal on a gold subscription, you are only turning it off on the gold you have at that time. If you go back a few days later or a month later and purchase a new gold subscription (because you are controlling when you make that
purchase) then the auto renewal turns back on. You will then have to have that auto renewal turned off again. The auto renewal is not turned off forever, it's only turned off for the current gold subscription that you have. Hope that explains it a bit more.

If you still have auto-renewal turned on, you'll need to call support to have them turn it off.

With the family plan I'm not sure if adding a card will just convert it to a single gold account, but the best thing to do is just turn off auto-renewal if you're not planning on renewing the family plan at all.

Auto renewal isn't on. I make sure I turn it off after each Gold purchase, not to mention I've checked to make sure the auto-renewal was turned off several times since the initial purchase since there is another bank account associated. Auto- renewal isn't
turned on and hasn't been on, no extra charges are on either bank account. Its just best for someone to close this question because this isn't going anywhere.

You are not able to transfer gold from one account to another account your gold subscription is forfiet, Make sure you have auto renewal turned off so when this subscription ends that it doesn't renew again.