What provides a higher lift to drag ratio, a thick laminar wing or a thinner wing with a vortex generator
You confuse turbolators with vortex generators. And then you misunderstand the function of vortex generators.

Turbolators trip the boundary layer and change laminar to turbulent flow in order to enable the boundary layer to remain attached over a steep pressure rise. That is definitely required at the Reynolds numbers mentioned (200,000 to 500,000) in order to maximize performance.

Vortex generators work in a fully turbulent boundary layer and re-energize it by mixing more of the outer flow into it.

Both increase the boundary layer drag but help to prevent early separation. Only over the range of that prevented separation they reduce drag.

The answer to your question depends on the Reynolds number. At 1,000,000 and above, the laminar wing should be better and if you add boundary layer tripping at the right chord station, it also wins down to 200,000.