Gents, the 777 has a function where by if you bring the RX waypoint to the top of the legs page 1L and engage VNAV then it will give you a 3 deg profile to that waypoint. That was option # 1.
Option #2 could have been to plug in the RNAV approach and use it for vertical guidance whilst conducting the visual approach..... what we call the Chinese glide slope on the side of the NAV display.
Option #3 could have been to look out the window and put the aiming point of 1000 ft in the bottom third of the windshield and keep it there and use the thrust to maintain a constant speed profile.
The inability to recognise a divergent approach (indisputable thru flight track v/s data) and the lack of a go around below a stabilised criteria height limit (again indisputable) is an indictment on the professionalism of the crew piloting the aircraft.
In response to BBK, I am in agreement with B-HKD. If you know anything about Korean law and their culture then these guys are toast.