Greetings,
I am not sure if Google is Reselling from Godaddy but I do manage mulple domains on Godaddy as well as Google. You can directly update your DNS from Google itself unless you have changed the default name server from Google to Godaddy. In both cases I can able to update your DNS records and update the TTL settings. No Matter what DNS records you want me to update (MX, SPF, CNAME, A, DKIM, AAA,...... ).
Please PM me to discuss and start the project asap. It will take just an hour time to update the DNS and may be up to 24 hours to DNS propagation. However generally both the Google and Godaddy DNS propagates within a few minutes. Please Message me to start.