This is a recurring thread on PPrune. It has been established you cant repeat the initial in EASA land although the Irish seem to consider themselves exempt.......However, nobody has posted that they have actually succeeded in repeating an initial in Ireland
I dare say this thread can continue with no definitive answer. My experience is that a doctor, hospital or other body in Germany cannot pass medical data to another such person but of course the patient has a right to see their own records. I cannot see why you cant go to whoever did the initial and ask them to give you a certified copy..... You may not get any renewal data without going to every AME and repeating the exercise, but this isnt beyond the realms of possibility. Might be worth asking the receiving Authority if this is OK, but as the CAA provides certified copies of licenses for the FAA it suggests they should be happy.
Any German doctors wish to comment?