NNT
I have made no speculation about the possible causes of the Garuda accident only posted the comment that, according to unofficial sources, the aircraft appears to have had fuel when it ditched.
As to the accident record of some of the Indonesian operators - that's just the point I indended - if you have to operate mainly in difficult terrain, in poor weather with limited aids then you can expect to have more accidents eg the stats show that, all else being equal, a non-precission approach is some 4 or 5 times more risky than a precission approach. You'll note that most of the accidents in Indonesia happen 'up country' at airports with very limited aids and in virtually every case no ILS.