The airmanship demonstrated on this flight is quite outstanding. The flight crew's awareness and problem-solving was top-notch in my opinion. They followed procedures as far was they would take them, but adapted to the situation as the "fog of war" (in this case "fog of the Antarctic") required. I'd buy these guys a round any day. Cheers!
The on-board database likely had the coordinates for the desired approach, but the world (possibly the satellites) moved a bit. The crew took note and found a way to adjust. Not what we want for commercial passenger operations, but as many other alluded to, in this environment, CONOPs etc, precisely why we like professional, well-trained military pilots to deal with such contingencies.