Well perhaps not. There was a historian by the surname of Alfred Lee and who wrote the book on Franklin County, Ohio history after the war and at least one place of his two volumes is located at the Ohio Historical Society.
The author has quite a different take on Morgan's escape from the Ohio penitentiary in November of 1864 and it's one that I agree with after checking into the author's story.
Franklin County, Ohio in which Columbus is located had many more Democrats than Republicans during the war. So many that Lincoln lost the election in Franklin County both times and lost more in the 1864 election than the 1860 election.
This is not to insinuate the Democrats were anti Union. However there were a great many more folks in Franklin County that were Southern
sympathizers than most people realize.
From past experience there was one major way for an escape during the war and that was gold. If you had enough gold you could almost name your own venture.
According to Lee, Morgan walked out of prison along with some others and in my opinion boarded a train and was south of the Ohio River before word got out that he escaped.
Why was the story told of him tunneling? General Morgan was a gentleman and if he had told of the ladies of Columbus who had collected enough gold to secure his escape and this would include bribing some of the guards then Secretary of War Stanton would have come down hard on the folks that made his escape possible. Morgan did not want that to happen and kept his secret to himself.
The Ohio Penitentiary in Columbus was torn down in 1984. I've talked to guards who were there about Morgan's escape and about the tunneling and they just laughed. It would not have been possible even in the days of the war one of them told me. Sewer systems and air chambers were not under his cell although they did say they did not know how he escaped. Today Morgan's jail cell is claimed to be at two locations. One just outside of Columbus at the Mott's museum and another place in Kentucky.
It is my opinion that Morgan walked to his freedom thanks to many women of Columbus and central Ohio.