There was a Leonard Case, born July 29, 1786 Westmoreland City, Westmoreland, PA. He was the father of two sons, William B. Case, born 1818, was the first native born mayor of Cleveland, OH. His brother, Leonard Case, Jr, was born in 1820 and this brother founded Case Institute of Technology in Cleveland.
This doesn't answer your question, but the Westmoreland, PA connection and common surname is interesting. Maybe these men are cousins to your Case line.