From today's paper...
There's a picture of a high-tension mast with a large piece of Citation wing jammed into it, at about 30 metres (100 feet) AGL. In the accompanying article they speak of "pilot error."
I don't think Citations are usually equipped with FDRs or CVRs, so that there probably will not be much more than guessing about what the crew were saying and doing as they entered what was reported as 100 metres (330 feet) visibility under VFR, but it should be fairly easy to guess it was something on the order of "Expletive deleted" (sound of impact).
What a waste. Divert to someplace with suitable weather, let the pax take a taxi to Trier, and catch up with them later once the fog had cleared... what's wrong with that? Hindsight: it's a wonderful thing!