Adam Czerniaków went to the gangster to get final money to pay the ransom. The gangster "house of ill repute" was at address Mila 18 - this was a reference to the Leon Uris story also of the Ghetto uprising.
Many of the German's rifles are Spanish 1916 7x57 Mausers, and not the typical Axis or captured rifles (e.g., VZ 24, WZ 29, etc.) used by German police or rear-echelon troops.