Account locked without email access

So my dad has locked his apple account after forgetting his password. But the email address registered to his account for reset, is to a closed/inaccessible email account. He never updated his Apple ID primary email address when he migrated to a new email service.

Struggling to find steps to get his account recovered and also change his primary email address. Is this dead in the water? Can is be resolved without visiting a genius bar, as my dad has mobility challenges?

Thanks.