'Bimbo' did not have the meaning it does today (an empty-headed young female).
When I was small (1960s) there was a comic character called Bimbo the Bear, who was certainly male.
General Sir Miles Dempsey, who commanded the British 2nd Army in North-West Europe in 1944-45, was apparently known as Bimbo, but I don't know why. There is a recent biography of him - perhaps that will explain. He is not a well-known figure, as he worked quietly in the background and left the public display to Montgomery.
Ann