Log into iCloud account without a trusted device

Sorry for the long post but I have tried lots of things already. My granddaughter broke her iPhone and is attempting to set up an old one. She forgot her iCloud password, but the has happened before, so we had set up me as a account recovery contact so she was able to change her password. She knows her phone number but doesn't have access to her phone. When she tries to log into her phone two factor authentication kicks in and sends a code to her old phone number. We have the option, eventually, of getting the code sent to her iCloud email, but she only had that set up on her old phone, so she can't access that.

So, she has no access to her old phone, no access to a previously trusted device and no access to her iCloud email. I have tried to figure out how to use the account recover contact to add a new phone number to her account but that only seems to be good for changing your password.

I started the account recovery process through apple but they are telling me it will be 7 days before we can add the new phone number to get a verification code so she can access her iCloud account. I have read every article, post and question I can find and cannot seem to find a way to use the recovery contact to get a code she can use to actually log onto a device. BTW have also completely reset an old iPad and tried to use my Mac to set it up for her so we could use that device as a trusted device. Still asked for two factor authentication. Also tried to set up her iCloud email on an iPad to get the code, iCloud rejected the password without her being logged into to iCloud on the device.

Any suggestions to get her on earlier than the 7 day waiting period.

Thanks