Bereavment fares and/or bereavement discounts are generally discussed with the airline (or agent) in advance of booking and ticketing. While it may have happened that some were given a bereavement fare and some reimbursement (for the difference between a bereavement fare and a higher paid fare) after the trip is flown in part (or in whole), I have never observed such a thing personally.

Bereavement fares or discounts don't always result in as much savings for last minute tickets as alternative fares/purchase methods. [Sometimes it is even cheaper to buy the miles from an airline and fly on a mileage ticket than it is to fly on a bereavement fare and/or with a bereavement discount on a regular paid ticket fare.]

If she manages to get a reimbursement after having flown the ticket in part or in whole, I would love to hear about it as it would be news to me.