If I was in the same situation as the OP, I would probably look into:

(1) pay to switch to later flights

(2) have them show up at airport late.... most decent airline check-in agents will let old passengers be re-booked on later flights without a fee

(3) buy daypasses so they can just relax for a few hours at airline clubs when they arrive at Memphis

(4) add one more night to the hotel stay(starting from the night before original check-in date)

(5) get $100 of quarters and send them to the slots