Nonsense. If anything, it serves as a distinction that under the existing Articles of War that civilian crimes could not be tried in military courts/tribunals. At that time failure of the commanding officer to deliver the suspect in question to civil authorities was itself an offense under Article 33:
If any commanding officer or officers shall wilfully neglect, or shall refuse, upon the application aforesaid, to deliver over such accused person or persons to the civil magestrate, or to be aiding and assisting to the officers of justice in apprehending such person or persons, the officer or officers so offending shall be cashiered.
Nevertheless, at the time (November 1861) the Confederate Congress had not authorized military courts to try such cases, that was remedied via legislation on 9 Oct 1862:
SEC. 4. The jurisdiction of each court shall extend to all officers now cognizable by courts martial under the rules and articles of war and the customs of war, and also to all offences defined as crimes by the laws of the Confederate States or of the several States, and when beyond the territory of the Confederate States, to all cases of murder, manslaughter, arson, rape, robbery and larceny, as defined by the common law, when committed by any private or officer in the army of the Confederate States, against any other private or officer in the army, or against the property or person of any citizen or other person not in the army."The war was far from over. Yet still no Confederate courts-martial for rape occurred.
An Act to organize military courts to attend the Army of the Confederate States in the field, and to define the powers of said courts.
"The men have behaved themselves the best I saw them either home or abroad. Every man has seemed to be on his good behavior since we entered Atlanta. The women have been dressed up waiting for our men to commence raping but they have waited in vain. There has not been a single outrage commited in this city, a circumstance that the people say they cannot say for the rebel army." - William Dunn, Surgeon, U.S. Army.
The soldiers "..blew out the parlor and passage lights, broke up the furniture, scattered the shrieking women like New York Zouaves before the bristling bayonets of North Carolina infantry, and to crown their unfortunate exploits, committed, it is alleged, an outrage upon the person of a "phrail phair one" named Eliza Liggon" - "The Richmond Examiner, June 13/18 1861, reporting on a visit of a detachment of McCulloch rangers of New Orleans, in the establishment of Clara Coleman at Richmond. Three men were held for rape