Carroll,
Shelby's report in the official records reads in part:
I would here state, however, that after all danger was over, by permission of General Price I sent Colonels Hunter, Schnable, Nichols and Slayback with their commands to North- western Arkansas to recruit both men and horses and gather up what recruits had been left when the expedition to Missouri commenced.
Guide to Missouri Confederate Units, 1861-1865-By James E. McGhee provides insight into Shelby's units that were furloughed after Price's Missouri raid of 1864.
He says that Hunter's regiment eventually regrouped and moved to Bonham, Texas.
Jackman's regiment under Nichols, seems to have reported back to the army at some point.
After furlough, Slayback's battalion is reported in the area of Yellville, Arkansas and surrendered as part of Jeff Thompson's command in northeast Arkansas
Slayback's battalion reported back to the army by mid December.
Memoirs of Colonel John C. Wright
I held my regiment together for several days for mutual safety as the enemy was still near at Ft Smith and Grayback guerrillas infested the area
Shelby at his request was left in the Indian nations to recruit and afterwards rejoined us with his old command in fine condition
He sent Colonel’s Schnabel Hunter Nichols, and Slayback with their commands to recruit and live on the enemy but this was the last of their service as organized commands
…and there we turned south east towards Arkansas
On reaching the line at Polk County I turned the boys loose to make their ways home
We reached El Dorado on 11/20 men and horses totally worn out
Series 1 - Official Records Volume 41 (Part IV)
SPECIAL ORDERS, HEADQUARTERS DISTRICT OF ARKANSAS, No. Washington, December 16, 1864. All officers and soldiers belonging to the commands of Marmaduke, Shelby, Clark, Jackman, Thompson, Freeman, Hunter, Tyler, and Wood will proceed to Red River and join forthwith their respective commands which are encamped in the country between Laynesport and the vicinity of Richmond, Sevier County. All officers and men couming either in regiments, battalions, companies, squads, or singly into this district from Missouri, unattached to either of the above-mentioned commands, will proceed forthwith and without delaying on the road to the headquarters of Prices armny, at or in the vicinity of Richmond, and will be assigned temporarily by the com- inanding officer thereof to one of the commands in that neighborhood or near Laynesport. Officers and soldiers of Dobbins and McCrays brigades, Fagans command, will assemble 1at Walnut Ilili without delay; those of Cabells brigade will report to Colonel Monroe, commanding brigade at camp twelve miles above Fulton; those of Slemons brigade at Hamburg, Ashley County. Browns battalion, which is hereby attached to Brooks command, will report forthwith to Colonel Brooks, near the mouth of Little River, Ark., or wherever that command may be. Officers of Prices army, including those of Major-General Fagans command, are forbidden to give furloughs without the authority of department or district headqn arters. By command of Maj. Gen. J. B. Magruder