The female names are pretty ambiguous in the Bobby Darin version of the lyrics. I think it is typical to read the lyrics and think that they are murder victims of Mack.

BUT, Mack the Knife is from the Threepenny Opera, written in 1928. The music is by Kurt Weill and the lyrics are by Bertolt Brecht. (Those are the same two who also wrote Alabama Song [Whiskey Bar] that was famously covered by The Doors.)

And if we look at the historic pre-Bobby Darin iterations of the song we can explain the female names.

For the record, Bobby Darin’s version mentions Jenny Diver, Suky Tawdry, Miss Lotte Lenya, and Lucy Brown.

Jenny Diver is one of the main characters in the Threepenny Opera, described as “a prostitute once romantically involved with Macheath; is bribed to turn Mack over to the police”. She is based on a real Irish pickpocket who was notorious in her day.

Suky Tawdry is another character from Threepenny Opera, described as “one of several prostitutes who associate with the gangster Macheath”.

Miss Lotte Lenya is different. Instead of a fictional character, that is the real name of the actress and singer who originally played Jenny in ThreePenny Opera in 1928. Her name was not in the original song lyrics, it was added by Louis Armstrong when he covered Mack The Knife. Bobby Darin based his cover on Louis’.

Lucy Brown is another character name. She is described as “Tiger Brown's daughter; claims to be married to Mack”. (Tiger Brown is an old friend of Mack and is the Police Chief in ThreePenny Opera.)

So, other than “Miss Lotte Lenya”, they are other characters in the opera. Mack does not murder any of them.