Are they genuine VW?
I had condensation in one of my front fogs, after I changed to LED bulbs. Transporter HQ swapped the bulb incase it was a faulty seal, but it still fogged up. I used a heat gun to gently warm it up, and it's never condensated since.
Bare in mind that I could remove the bulb to allow for the moisture to escape whilst warming. I'm not sure if that's possible with a Drl if they are a sealed unit?