Regaining access to an Apple ID

My niece has an iPad mini. Her Dad bought it for her in Dubai and she's used it for a few years now. At the time I don't think he realised the importance of the Apple ID, etc... (none of us did!!) and he created a Yahoo email account using his daughter's name (*****@ yahoo.com) because he needed something for the registration. We can't get into the Yahoo email account as it has only 1 recovery method, a mobile number which is now obsolete (we know the number but we can't receive a reset code at the number). I also have no idea what birthdate he put into the Apple ID because we've used Iqueshi's real birthdate and it's not working. We've also tried her Dad's birthdate, and several other alternatives, and none of them work.

To make matters worse, we thought we could just do a factory reset and start from scratch - we had no idea that Apple would basically brick the device if we did that. So at present we have a factory reset iPad which we can't activate, and trying to regain access to the Apple ID is not working because the email address is not accessible and the date of birth is not agreeing.

How does Iqueshi get in to her Apple ID in these circumstances?

(As you can tell from the email address associated with the Apple ID - it really does belong to Iqueshi Aureada, and she is Iqueshi Aureada, and she can provide proof of same.) Apple can also verify, if they want to, that we're accessing from the same network connection it's been used on for a couple of years, so it's not been stolen and taken somewhere else. So there are ways and means for Apple to verify it's her account.

We look forward to hearing how you can assist with this dilemma.

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