what was the WW II German red cross hewer used for army or red cross, and why was the blade flat on the end?

Answer 1

It was a dress dagger and served no practical purpose, its design probably reflects some nazi fantasy knife for medical use, but no other country in the Red Cross at the time had a knife in their costume design.

The Red Cross had no military connection per se as it was aligned with the International Red Cross of the day.