Maybe they operate behind the curtains, but they don't have any real 'turf' there. The thing with Great Britain is, is that there already is a pretty brutal and powerful presence of homegrown and other foreign OC groups. But it's definitely possible that some members of the Ndrangheta or the Camorra supply cocaine to the groups in Britain.
As for Germany, the Ndrangheta is very strong there, but also behind the curtains. The criminal activities of German Hells Angels, Albanian, Turkish, Russian and Serb mobs or Mhallami family clans are much more visible.