First choice is try to convince him to cancel.
e.g. "Are you sure you are wanting to come to Memphis, it is Very Far from DC..."
Promise him a full refund of your fee, regardless of your policy.
2nd choice is to let airbnb help you, you may get lucky.
3rd choice is accept him, but take contral.
You've been in the business 3 years, so you do understand that many foreigners' phone service does not work in the US.
Inconvenient, but not nefarious. But you must control checkin time. Give him a window of time. "Unless we hear otherwise, you can check in at 5-6 pm ..."
4th choice is to cancel him blocking the time period, getting penalized and losing your superhost ranking. But that is a small price for your well-being. It's your house, screw Airbnb.