I am skeptical of any theory involving an Asia overland route, too many radars and people that would have spotted it.
My goofy conpsiracy theory is pilot went west over Andaman islands, turned south at Maldvies and ditched plane off Annu atoll where he is rescued and flew onward from Gan airport.
Motive: some government wanted the 20 passengers working on electronic warfare/radar defense dead.
Then I was dissuaded here by freepers who knew the field.
I do think the plane made it to either Somalia, Pakistan or Iran.