Craven said he was inspired to write the film when he saw a tramp with long fingers, when he was a child. Before I saw the film, or knew about Fred K I had a horrible dream about an old man with really long fingers. I told my sister about it and she said she had dreamt about the same man. I recalled that there had been a girl in the dream with me. Even longer ago, before the film was ever made I designed a character in my notebooks who wore a wide brimmed hat, had a claw on his right hand and had a stripey top. I even think the colours were close enough. But my guy wore a visor and was more a space age type. So was that a mix of V and Nightmare on Elm street? They wore visors on V.
Maybe this Kruger is real. Look at the name Robert Englund. Some of the oldest names for demons are like Robert. "Robet" is an old jewish word for demon. Then there's Rabisu in the same language which was a "crouching demon" They may stem from the oldest name of the devil; Rahab. or RHB, given they have no vowels. RHB sounds alot like Rob. Rahab was a sea serpent by the way. So fits with V too.
Rahab is mentioned in the Talmud and the Old Testament, and its etymology is given as 'noise,' tumult' or 'arrogance.'
This name originally designated the primordial abyss, the water-dragon of darkness and chaos, and so comparable to Leviathan and Tiamat. Rahab later became a particular demon, inhabitant of the sea, especially associated with the Red Sea, in this case sometimes associated with Leviathan.
Then we have Bob from Twin Peaks.