As you indicated, J Alphonse Prud'homme was at Oak Hills and Elkhorn, with the 3rd LA Infantry in Aug. 1861 and Mar. 1862. W W Breazeale, however, was not at Elkhorn (Pea Ridge) as he had resigned his commission with the 3rd LA Infantry on 24 Sept. 1861. As to Prud'homme, he was wounded and captured at Elkhorn (March 1862), and was mentioned in the OR reports on Oak Hills (Wilson Creek) for his bravery. Although not absolutely sure, I believe he went home to recover from his wounds on being paroled, and did not re-enlist in the 3rd LA when his one year enlistment was finished in April 1862.

In May or early June 1862, he obviously began working with the two Breazeales (WW & WO), SC Furman, JD Blair, FA Prud'homme, and JF Scarborough to form Breazeale's Battalion of Partisan Rangers. In September 1862, this Battalion (5 companies) became the core for the 2nd LA Cavalry.

Very best

Don Parker