Reading through the GFiber TOS it's not clear that you must use a Google account - they refer often to "the email address used to setup your account" but you ca

Reading through the GFiber TOS it's not clear that you must use a Google account - they refer often to "the email address used to setup your account" but you can have a Google account with an email address not serviced at Google. So if you're willing to have multiple accounts it seems doable.