Wasn't Donald Dohner the true GG1 designer?
I believe Classic Trains had an article about Dohner and his role in the design. I'll see if I can find the patent for the GG1 design. and look for his name. I believe he was working at Westinghouse at the time, so Westinghouse might hold the design patent.
Back then, however, the chief designer got the credit. The first line in the title is R.G.F. LOEWY ET AL. You probably can't read it but the inventors are listed as Raymond G. F. Loewy & Warren R. Elsey. Chances are Warren might have done the actual design.