Here are two accounts of Rousseau's raid involving different soldiers with similar names belonging to the 6th Ala. Cav. Perhaps service records better identify these men.
One account, of activities that occurred July 14, 1864, was written by Samuel Coleman of the 6th Ala. Cav., and published in the Confederate Veteran, Vol. 20, No. 9, (Sept. 1912), Page 410. The online service database at ADAH for Samuel Coleman indicates Co. P, obviously an error. Don't find a record in the NPS online soldiers database for this man.
(https://books.google.com/books?id=7m1AAQAAMAAJ&source=gbs_navlinks_s).
Another account, an obituary for Samuel T. Coleman of Armstrong's Co. (K), 6th Ala. Cav., who died July 15, 1864, written by an unidentified officer belonging to that regiment, was published in the Selma Reporter July 27, 1864 (see below). There is a record online in the ADAH service database for a Samuel T. Coleman, but it does not appear to be the same man, based on unit (41st Ala. Inf.) and age. He is listed in the NPS online soldiers database, Co. I, 28th Ala. Inf., but don't find a record referencing the 6th Ala. Cav.
"A more noble, patriotic soul never faced our enemies than that of Samuel T. Coleman, who died on the 15th of this month, (July,) at Greensport, Ala., from wounds he received in the fight at Ten Islands on the previous day, July 14th. His age was 18 years. He volunteered his services at the age of 16, when he promptly enrolled his name among the Dallas Warriors, Capt. Hopkin's company, 28th regiment Alabama Volunteers, in which he remained, faithfully performing his duties as a noble little soldier, until he was compelled to receive his discharge on account of his failing health, "And with reluctance he received it."
He then remained at home until April the 1st, 1864, when he joined (this) Clanton's Cavalry, 6th Alabama Regiment, Capt. Armstrong's company, in which he remained up to the time of his death, and was one of those noble little spirits that never deserted the post of danger and duty.
He acted very bravely and gallantly upon the field. The morning he was wounded he was on the top of Lost Mountain, and was asked to surrender by the enemy, which he would not do, and was then shot in the arm, and was again asked to surrender, to which he scornfully turned his little head and was in the act of walking off when he was cursed by the enemy and fired at again, which ball hit him in the hip and proved to be a mortal wound.
He then fell and lay upon that mountain, (where he nobly sacrificed his life in defense of his own native State, Alabama, and loved ones at home, rather than surrender to the unmerciful enemy who was seeking to destroy our homes,) all day exposed to the hot sun until night, when he crawled down and was carried to an old citizen's house where he was carefully provided for, and every attention that patriotic sympathy could suggest was bestowed upon him by that family.
He was in full possession of his sense, and well aware of the nature of his wounds. He was calm, collected and no murmuring, viewing his approaching death with the fortitude of a noble little soldier and the resignation of a Christian. Enviable fate! In the prime of youthful strength, at peace with God and man, he passed painless from this to a far better world in the discharge of his duty and the exhibition of the most patriotic courage. There is mourning in his devoted family and the wide circle of his friends. All who know him deplore his loss, for he was a worthy and amiable young man."