I believe we've had direct quotes in the books that DFs are extremely rare amongst the Aiel (from Hadnan Kadere, I think, and maybe elsewhere). More importantly, I believe the harsh tests of Rhuidean weed out any potential DFs from becoming clan chiefs or Wise Ones. You need a strong will to pass those and DFs are inherently weak.

I don't discount the possiblity that the harsh new reality Rand brought to the Aiel might put a Clan Chief or WO over the edge (probably with a misguided aim of preserving their people and culture), much like it broke a percentage of the spears. Still, I'd be very surpised if Sorilea, Rhuarc, or any of the other prominent Aiel characters turn out to be DFs. If they are, they're playing a very deep (and mostly incomprehensible) game.