Two final points:

1. Yes, as an act of desperation the Confederacy did pass a law to enlist slaves as soldiers - on March 13, 1865, a month before the end of the war. Virtually none were actually ever enlisted.

The text of this act is available HERE and I call your attention to SEC 5:

That nothing in this act shall be construed to authorize a change in the relation which the said slaves shall bear toward their owners, except by consent of the owners and of the States in which they may reside, and in pursuance of the laws thereof.

No mention of emancipation in exchange for military service.

2.Yes, its true that a few deluded, terrorized, uninformed or coerced Blacks did support the Confederate war effort.

However, the 186,000 Blacks who served in the Union Army - 24,000 from Louisiana, 17,800 from Mississippi, 20,000 from Tennessee and from the other southern states in proportion - point up that the number was small & statistically insignificant in light of those who fougt AGAINST the Confederacy.