I would only explain the situation, as here are many items found in untouched condition because stored in houses for long time.
When piece was found in a SS marked frog doesnt mean it automatically, it was there from war. So Your 41ddl piece as mentioned before for me is a normal WaA piece, ordered by Army and has nothing to do with SS, same as i dont believe Your opinion about engraving there a DH for property stamps after rework. Partly because there is no sign of propper reworking. The piece has not origin grips but no other signs of reworking.
