Flight to JFK on marathon day?

My parents have booked a flight to see me and they fly out from JFK on sunday. Unfortunately they didn't realize it was marathon day so now they're scrambling to find alternatives. They're leaving from Linden, NJ (unfortunately the flight route doesnt leave from Newark instead💔) and their flight from JFK leaves at 6 so they'd have to be there at 3 as its an international flight. Any advice or suggestions on what to do?