Dennis,
I'm always skeptical of info in the POW documents. Undoubtedly many mistakes are made by the person recording the info and, I believe, incorrect or inconsistent info given by the prisoner. When William Penn Adair was captured at Locust Grove, Cherokee Nation, his various POW records say either 1st Cherokee or Arkansas Cavalry -- I don't think the person recording the info would have known that the Cherokee regiments were originally authorized at Arkansas regiments so I assume that info came from Adair himself. I think bushwhackers, when captured, would give the name of a unit with the hope of being treated as regular soldiers -- I think men with Quantrill, Livingston, etc. claimed to be in Watie's 1st Cherokee Mtd Vols for this reason. Of course, mistakes could also be made in recopying info as prisoners were transferred.

In this particular case, the reference to the 3rd Arkansas seems to be Gratiot's 3rd Arkansas Inf State Troops under Brig.Gen. N.B. Pearce. (see my other post re the Frontier Guards.) Oddly, I didn't find any of the 5 persons you mentioned on the roster for the Frontier Guards but they may have come from other companies in Gratiot's regiment.

Ken