Chris,
Thanks so much for this post. Fascinating stuff. I have been doing some research into that squadron myself, and I found this material very interesting. There is a very good article published in Aviation Quarterly which is basically a summary of the memoir written by a member of the Escadrille Cherifienne, Col. Paul Ayres Rockwell.
Dale L. Walker “Paul Ayres Rockwell, Moroccan Bomber: American Fighters in the Rif War.” Aviation Quarterly vol.5, 2 (1979).
Rockwell in the memoir speaks highly of Sussan. I don't know if you already knew that the commander of the squadron, Col. Charles Sweeny (also sometimes spelled Sweeney) was one of Hemingway's closest friends. I am precisely doing research for an article I am trying to write on the subject. I would be happy to send you a scanned copy of the memoir summary article if you are interested.