Fuel leak
The massive fire after landing and the way the fire quickly engulfed the aircraft wing, clearly shows that there was a huge external fuel leak. The entire leading and trailing edges were on fire. As there are no external fuel lines in this area, how did the fuel get sprayed in all these areas. This raises the following questions.
1. Did the crew shutdown the engine on getting the "oil" low press warning.
2, If so why they elected to continue to fly to SIN when they were much closer to BKK. SOP demands that aircraft with one engine off must divert to the nearest suitable airport, which was BKK.
3. It is also possible that they did not shutdown the engine, but this resulted in the entire wing getting soaked in fuel and the ensuing fire after landing.
4. The decision not to evacuate was probably the pilot saw that the entire ground below the fuselage was on fire (as it can be seen by the stab mounted camera). There is no point in sending pax through the slides into a raging fire. If that was the reason for non-evacuation it was correct decision. But they have relied a lot on their luck, and the end result was fortunately a happy one.
5. One heck of a lucky plane load of passengers.