Gibbs and Mr. Flores would not have been allowed to have a conversation at the Tomb of the Unknown. The guards insist on complete silence.
When Gibbs is having his flashback with Pvt. Matteson fixing the Jeep, there is a key in the ignition of the Jeep. Military jeeps did not have keys, they have small levers that you press together to start the vehicle.
A C-130 would not have the range to fly from Kandahar to Dover AFB, even with a stop in Europe.
While Jimmy and Ducky are working on the remains, Jimmy removes his glasses without taking off his gloves. He then puts the glasses back on.