The survivors would probably end up in Jutland or Norway, maybe Sweden due to the currents.
The main wind pattern is also western, but with prevailing eastern winds, they might end up in Scotland, depending on the vessel. The Jutlandic coast has experienced a large number of shipwrecks in the past.
Even if a boat gets out on the open ocean, the Gulf stream flows northeast, so there are very small chances to get to Sub-Saharan Africa.
So the answer would be: (a), very small but depending on the survivors' ability to navigate and the wind direction. (b) None.