I don't think the throttle was stuck otherwise the PF would have said something when he was flaring the aircraft. However, I would like to know if there could be a mechanical disconnection from the thrust levers to the potentiometers. In this case, the PF would retard both throttles to idle, but Eng 2 would remain in Climb because the potetiometers wouldn't receive the order to go to idle.
I know that investigators found the thrust lever in climb but with the force of the impact the throttles can move around.
I fly CFM engines , so I have rpm instead of EPR, but it looks like the EPR indication is not very clear of the status of the engine.
Check Six, Krueger...