Brandon Peterson has never actually worked on Promethea but he was slated as the artist to do it before JH Williams was chosen.A small quote from Brandon
I was the artist on Awesome's Glory, along with Chris Sprouse on Supreme and Steve Scroce on Youngblood. When Awesome went out of business, Wildstorm contacted Alan and used the basic ideas from those books to form the ABC line. Chris went to do Tom Strong (the Supreme equivelant), while both Steve Scroce and I declined working on our equivelant books (Top 10 and Promethea) as we had already accepted Marvel work after Awesome fell. I did get offered the book, but I never did any substantial work on it.
and here is an interview with someone else who has never worked on Promethea but collects original Promethea artwork