IOTL, the proposal by Confederate General Patrick Cleburne in January of 1864 to free slaves and enroll them in the Southern army was rejected by his fellow officers at the Army of Tennessee (although there were some generals who expressed support). More importantly, when the militant pro-slavery general William Walker angrily dispatched a copy of the proposal to the War Department in Richmond, President Davis and Secretary Seddon immediately ordered all discussion of the proposal to be terminated. Consequently, historians never knew the proposal had been put forward at all until decades after the war. Some historians believe that his proposal resulted in Cleburne being passed over for corps command for the remainder of the war.
By the time the proposal was made, Cleburne had already established a reputation for himself as the finest division commander in the West, and perhaps the finest in the entire Confederacy. He had fought gallantly at Shiloh, in the Kentucky Campaign, at Murfreesboro, at Chickamauga, and at Missionary Ridge (where his division held its portion of the line against heavy odds even as the rest of the army collapsed). He had saved the Army of Tennessee from possible destruction through his rear guard action at Ringgold Gap after the disaster at Chattanooga, an action for which he had received the official thanks of the Confederate Congress.
What if there had been some sort of leak and word of the Cleburne proposal had gotten into the newspapers and became known across the Confederacy?