Using classic Outlook for Windows in business environments
I'm curious when you say "refuses the secondary back up phone number requested", did you provide a good phone number and Google refused to accept it? I set mine up so it would text a cellphone and/or voice call a landline phone, plus, I can add more of them of either type, so I'm a bit astonished if Google refused to accept a phone number. Let me add that Google will work with an Authenticator app, there are many available for both iOS and Android. Please don't bet the whole farm on that list of one-time numbers.