Airbnb will determine if the guest fits the "extenuating circumstances" policy. During a horrible storm in DC a guest cancelled the day of because of weather. But the weather was mild here in Durham. Since the roads weren't closed and businesses were open in DC, they said she should have been able to travel and denied her refund claim. She then reached out to us to seek the full amount, which we declined.
Don't speculate on if a guest will be reimbursed. You have a cancellation policy and Airbnb will honor it. If Airbnb wants to refund, that's on them.
Someone will soon say that weather conditions you don't want to deal with are covered with Travel Insurance, which is true. If the guest didn't procure it, that's not the fault of the host.