I am sure airlines are updating their training manuals after this incident. But any professional with common sense would already have done it differently.
1hr - low oil warning -
Action: Monitor oil pressure
Possible action: 1hr into 12hr flight, go back to SIN and get it checked.
2hr - engine vibrations -
Action: Idle, monitor fly for another 2 hours with idled engine
Possible action: Idle and land immediately
3.5hrs - Dump fuel
Action: Say "Negative" to assistance
Possible action: Ask for assistance.
They took three perfectly valid (sans commonsense) decisions, non-evac is just icing on the cake.
IMHO professional pilots and silent because that would be like GOP commenting on Trump scenario.