No, you're right that it's credited to Willie Dixon,
Posted by Joe on March 19, 2018, 3:47 pm, in reply to ""Little Red Rooster" is a Willie Dixon song"
so I was wrong there, but I do think that I remember one of them saying that a third party either wrote it or taught it to them. I can't remember now if I heard Willie Dixon saying that he learned it from somebody else or I heard Wolf say that it was from somebody other than Willie Dixon. I think it was Wolf that said it though.