No, he was the Chief Test Pilot and lead pilot engineer on the project. There was no single "brain" behind the A320 - it was a long-running collaborative project, as I said above.
Chief Test Pilot for A320 development was Pierre Baud.
Chief of Engineering was Bernard Ziegler.
Gordon Corps was a Flight Test Engineer.
Pierre Baud became Airbus Chief Test Pilot in 1978, succeeding Bernard Ziegler (A300 Chief Test Pilot) who moved over to Engineering. After the A320, Mr. Baud remained as Chief Test Pilot on several programs until 1994.
The A320 first flight was piloted by Pierre Baud, and co-piloted by Bernard Ziegler. Gordon Corps was the observer.