1) Seen by whom? Some free blacks did indeed try to join the rebel army and even tried to drill together, they were not accepted into the Confederate.
2) Some free blacks did indeed offer their services to the rebels at the beginning of the war, but none were accepted. The Governor of Tennesse DID NOT authorize blacks in the rebel army, in June 1861 or any other time. Please provide a link to information indicating that he did. Please provide a link to a Confederate order of battle listing them. In any case, blacks in the rebel forces were expressing banned by Confederate law until March 1865.
3) Free blacks in Louisiana did indeed form two regiments for the Confederacy, but the rebels refused to accept them so they joined the Union Amry when General Butler captured New Orleans. If you want to count them as rebels, knock yourself out.
4) None of those blacks who were formed into rebel companies at the end of the war were ever armed, even in drill, and none saw combat.