I would avoid doing exams and getting a license from the German LBA as they are much more difficult to deal with than the CAA. Apparently you have to sit approved courses to even sit the Part 66 exams; you can't self study and just turn up and take the exams like you can with the CAA!
In the UK there are also exam venues in Oxford, Luton, and Prestwick (Scotland)
https://www.caa.co.uk/Commercial-ind...xam-timetable/