Alan, most honest students of this subject do not state there were separate black units, the famous Lousianans having quickly switched sides, nor that the number of combatants of color was anywhere near the bloated numbers floated by some. I do believe there were isolated incidences of black Confederate soldiers who were accepted by their comrades, but not recognized by authorities, for the reasons so often stated.
For one lone example, Bill Yopp started out as the servant of a lieutenant in the 14th Ga. He later was enlisted as a musician. While not a line soldier, musicians were used as litter bearers in battle. After the war, Mr Yopp became a successful business man, and assisted his former owner, who had fallen on hard times. He is the only black buried in the Confederate cemetery in Marietta, Ga.
The most famous example of actual black soldiers is the group enlisted by Nathan Bedford Forrest. When he surrendered, there were some sixty of them in his personal escort, of whom he said, no finer Confederates ever fought with him.
The gentleman in the You Tube segment is a little too smug for my taste, whatever the veracity of his presentation. I offer no opinion on that either, but I did notice that the comments section was blocked. Stan