It turns out that he was a deserter and not a Jayhawker. The following is from a letter Captain Samuel Haas wrote after the war:
Samuel Haas to Colonel E. F. Brian, Secretary Board of Pension, March 4, 1912
“Now let me tell you the facts. One Lieutenant Joe Clark, and Privates Neville Johnson and Don Louis Deville, right after Todd was arrested through order of Gen. Richard Taylor, these three men among a dozen or so of others deserted but the most of them came back. I sent back for them and made good soldiers of them with the exception of the three mentioned, Clark, Johnson and Deville as these three were with the enemy as far as New Orleans, if my memory serves me right. Later they were captured. Clark was courtmartialed and shot and Deville and Johnson were under arrest but throught [sic] my influence and that of others they were both reprieved and sent back to the Company where they made fair soldiers and remained true to the Confederacy for the balance of the war."
SOURCE: Pension Application File of Neville Johnson, Louisiana State Archives