No marks inside?
Maybe photos of the neck-to-body connection inside might give some clue.
Dowel stick attachment looks similar to an old Waverly but it is not exactly the same. My instinct is that you are correct that it could be East German but I have no evidence to support that. It looks to be solidly built but not expensive.
Most, if not all banjos that come out of the GDR have a 'zero' fret just past the nut.
'Good Wednesday Morning' 7 hrs
'Poltergeists ?' 9 hrs
'Eye Bleach' 10 hrs
'Goodbye Liza Jane' 10 hrs