It sounds to me like the controller couldn't understand a lot of the rapid AI 101 dialog but he was doing a great job trying.
Normally the situation is reversed after a 15 hour long haul into JFK.
Don't forget these guys have been working too long, probably with little rest onboard, and as usual when stuff gets busy and the feeling of overload occurs, you look for the easiest way out. Nit pick later.
7200kg is about 30 minutes of holding/diverting fuel, before you land with final reserve. (Not 72 minutes!)
Perhaps I'm assuming too much -- does ETOPS on a 777-300 require an operational APU for dispatch?
The 777 doesn't need much for EDTO. Most failures, including APU, allow 180 minutes.