"I can't imagine a white soldier going into battle with his slave in tow and the slave not be armed, can you"?

Two examples of Black Combatants from the Official Records. The 1st man mentioned was obviously a slave. The two men mentioned in the 2nd report may well have been "free men of color", and duly enlisted. The 1st Virginia Cavalry had such a man, Bugler, James Humbles.

Report of Confederate Colonel Thomas Munford on an engagement with the Virginia Unionist Partisan unit “The Loudoun Rangers.” January 25, 1862.War of the Rebellion: Serial 016 Page 0749 Chapter XXIV. CAMPAIGN IN NORTHERN VIRGINIA :

On the 31st the brigade accompanied General Stuart on a scout to Chantilly, picking up 200 or 300 prisoners. A portion of the Twelfth, under Lieutenant-Colonel [R. H.] Burks, captured one company of the Tenth New York Cavalry without firing a gun.
On the evening of September 1, while our troops were engaged on the Ox road, near Germantown, my regiment was ordered to Leesburg to capture Means and his party.
About 11 a. m. the next day I arrived at Leesburg. Learning that Means was in the town, I cut across from the Dranesville pike and entered the town by the Edwards Ferry road. I succeeded in surprising Means’ party, Means himself escaping. He was supported by Major Cole, of Maryland, with about 200 men, on the Point of Rocks road. Without halting in the town I pressed heavily upon him, and soon succeeded in routing his command after a heavy skirmish, and pursued them as far as Waterford, 7 miles. My command amounted to 163 men, about 40 of which number, including Captain Dickinson and Lieutenants [W. R.] Beale and [A. D.] Warwick, did not join in the charge from some cause not yet explained. Had they followed their comrades in this bold charge I do not think a dozen of the whole Yankee command would have escaped being either killed or captured. As it was, we killed 11, wounded 9 too badly to be sent away, besides some 10 or 11 who escaped badly wounded and sent off 47 prisoners, including 2 captains and 3 lieutenants.
In this charge Lieutenant J. O. Davis, of Company E, was killed while gallantly leading the advance of his company. Lieutenant John O. Lasley, of Company K, had his arm fractured by a rifle-ball, Sergt. Charles Spears, Company C, was killed. Private N. McGhee, Captain Dearing, of Company F, and John Merryman, of Company I, were badly wounded. It is proper to report that Edward, a servant of Private English, Company K, went into the charge, following his master, gun in hand, and shot the notorious Everhart, who was left in Leesburg, badly wounded.
* * * * * * *
I am, Major, very respectfully, your most obedient servant,
THOMAS T. MUNFORD,
Colonel Second Virginia Cavalry.
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The second is a rather lengthy report authored by Thomas J. Jackson 2 weeks before 1st Bull Run. It can be found here :
War of the Rebellion: Serial 002 Page 0186 OPERATIONS IN MD., PA., VA., AND W. VA. Chapter IX.

An excerpt reads :
"Colonel Stuart reports his capture of an entire company (the Fifteenth Pennsylvania Volunteers), with the exception of the Captain. Three, resisting, were killed. He further reports that "one of the enemies was killed by a negro of Captain Carter's and one of Captain Patrick's Company." The following is his list of prisoners: Forty-three privates, Fifteenth Pennsylvania Volunteers; one-second lieutenant, one surgeon, one (position not known), but all of the Fifteenth Pennsylvania Volunteers; one Private First Wisconsin Volunteers; two Privates Second U. S. Cavalry, mounted and equipped; making a total of forty-nine. He reports one wounded and two missing. The enemy, he states, entered Martinsburg at 12 n. to-day".