Just wondering if there was any updates on the "mystery" spark plugs?

Both, the VW dealer and Bosch Service in Germany, found the part number (Bosch and VW part number), but couldn't find out for what car or engine those spark plugs were. They also didn't have any info on these spark plugs, as they have never even seen them.

So if I wanted to buy a set the Vw/Audi dealer couldn't order them for me?

The Bosch guy said the same thing.