Scott,
Not sure what you're asking.? The article you reference has to do with adding an alias for a subscriber/member to be able to send?from an email address other than the primary email address for their account.? This has nothing to do with the email address of the group itself (<groupname>@groups.io, for instance).
There is no way that I know of to have an alternate or alias for addressing email to the group.? What would an alias be needed for?
Thanks,
Toby
Toby Kraft