Activation Lockout Issues

I am trying to help a lady whose husband needed to do a restore on his iPad Air. He was desirous to reset his tablet to factory settings and start over. So I backup up his data to the cloud and proceeded to reset his iPad. After it was reset came the time to activate the iPad, but it was locked to his account. I entered his Apple ID account and password, but it was set up for two-step verification. The problem is that his trusted phone number is one from a company that he used to work for and he no longer has access to. In short, we cannot get a verification code from that source. So I tried to get the verification code sent to his email address. The problem is that he only had his email account setup on the iPad itself which has now been erased completely and ready to setup again manually. So I downloaded the iCloud app on my PC in an effort to login to his email account to get the verification code for the activation. But the app requires the same verifications as the iPad is asking for. I sent a request to use a new trusted phone number (his wife's phone number) but it says that it will take 24 hours for her to get the instructions to help verify the account. Is there any way to get this account verified so that I can restore this man's iPad? What additional information will I need after 24 hours when they are supposed to contact his wife as the new trusted phone number? I had no idea that he had two step verification setup to an unusable phone number or I would have turned that off prior to erasing the iPad. Any suggestions?