The more i think about and the more i think you are right Paul... I was more collecting informations than on a criticise time those last days 
The two "snake" are obviously dammaged and more broken than flattened probably cause of their wooden construction.
The others, steal ones, are flattened and dammaged like "B3+CL", or probably repaired like "9K+FH", or bad quality shots like white "17+S" which could have the late version navigation light at the end cap.
So only remain one question did the wooden "snake" rudder got any navigation light?
From the above photos they clearly dont have any transparent end cap nor any late external navigation light... Perhaps because they were experimental and thus not suited for combat units at least at the begining? One more reason to think that none of them were delivered to Kdo.Nowotny... (Hehe time to return to original topic)