would it be ok to pile drive footings insted of waiting one or two years for hardcore and top soil to settle

The decision to use piles or footings is determined by the ground type in your area, in BKK and the surrounding region it's invariably piled due to the ground being deep clay.

If your area would normally use footings then there's no reason to pile, simply dig through the fill and then into the original ground to the same depth as would be normal for footings.

Assuming he's local ask your contractor what he recommends.

Why 1 or 2 years. ?? If you mean you want to build sooner than later you just need to go to the original consolidated ground.

The driven piers don't necessarily extend to bedrock. They are surface-bearing, relying on friction between the pier surface and the clayey soil. It's the straw in the chocolate malt scenario... same concept. Search on the subject in this Forum, as its been covered many times. But, bottom line, you don't have to wait to start.