Apologies if I am stating what you already know.
the way the Bi-Xenon lights work is that a shutter mechanism reveals more of the bulbs light dispersion which makes it brighter and throw the light higher down the road. It literally is like a mechanical eyelid that is halfway closed for low beams, and retracted for high beams. The inner section of the 2006 models is blank and non-functional, so don't look for it to light up. Model years thru 2005 with HID setups had bulbs in the inner section of the light housing, but it only worked as a 'flash to pass' function.
I guess the the point is that your shutters are malfunctioning somehow. I feel like that may be easier to fix than trying to retrofit halogen bulbs in there, since you would need a set for the lows and then you would need a set for the highs. Nothing is impossible of course, but you would likely need a donor assembly and some fabrication to get all this working. Also you would need to figure out the relay and how to trigger it.
They make aftermarket Bi-Xenon setups, but there again it would take a fair amount of modification to get that working correctly. I would recommend fixing the shutters.