Pvt. Ricardo gravestone.
Sergeant Sam Ford, a private known only as Richardo, and two other soldiers whose names have been lost to history (one of these is probably John Donaldson, based on an obituary which appeared in a Tucson newspaper. However, there is nothing at the gravesite itself to indicate this, and it is unknown as to which, if either, of the two unmarked graves is that of Donaldson).
Sources:
Wikipedia (https://en.wikipedia.org/wiki/First_Battle_of_Dragoon_Springs)
https://www.mycivilwar.com/battles/620505d.html
Finch, L. Boyd. Confederate Pathway to the Pacific: Major Sherod Hunter and the Arizona Territory, C.S.A. Tucson, Arizona: Arizona Historical Society Press, 1996.
Horn, Calvin P., and William S. Wallace, Editors. Confederate Victories in the Southwest: Prelude to Defeat. Albuquerque, New Mexico: Horn and Wallace, 1961.
Kerby, Robert Lee. The Confederate Invasion of New Mexico and Arizona, 1861–1862. Tucson, Arizona: Westernlore Press, 1958.
Masich, Andrew E. The Civil War in Arizona. Norman, University of Oklahoma Press, 2006.
Rodgers, Robert L. "The Confederate States Organized Arizona in 1862." Southern Historical Society Papers, Volume 28 (1900).
Sonnichsen, Charles Leland. Tucson: The Life and Times of an American City. Norman, Oklahoma: University of Oklahoma Press, 1982.
Sweeney, Edwin R. Cochise: Chiricahua Apache Chief. Norman, Oklahoma: University of Oklahoma Press, 1995.
Walker, Charles S. "Confederate Government in Dona Ana County As Shown in the Records of the Probate Court, 1861–1862, New Mexico Historical Review, Vol. VI (1931), pp. 253–302.