Had they declared emergency earlier as they should have, possibly stating how much endurance they have left, it would have been a trigger for the controller to get the other aircraft out of the way to get the LAMIA in ASAP. The outcome may very well have been different in that case. But as it sounds, they kept that vital information from the controller right until the point where the tanks were empty and the engines were flaming out
That's about it in a nutshell. I really feel for that controller.