Thank you Bruce, as always. The information helps fill in the lack of information on the encounter in Dyer and the OR.
With regard to the grave, I am going to visit the landowner the next time I am in the Rolla area to see what information they may have on the burial. I am leaning more toward the theory that the Confederates buried there were POW's who died in Rolla before they could be shipped to St. Louis by rail.