Company D, 11th MSM Battalion/12th MSM Cavalry was not transferred into 3rd MSM Cavalry (New). As is indicated by the rest of your post, Company D was integrated into what became the 5th MSM Cavalry, where it was redesignated Company K, 5th MSM Cavalry. 12/A became 3/K; 12/B became 3/L; 12/C became 3/M.

Company D, 12th MSM Cavalry and Company K, 5th MSM Cavalry are the same unit. There is no daylight or difference between them.

It is a myth that the 12th MSM Cavalry was absorbed into the 3rd MSM Cavalry. Three companies of the 12th MSM--a minority of the regiment--were unified, on February 4, 1863, with the 10th MSM Cavalry, with the combined unit afterwards being redesignated the 3rd MSM Cavalry (New). This new unit then served the next year and a half in SEMO and was moved out of the area in the fall of 1864.

Empfield/Flenge company was not one of these companies in the 3rd MSM Cav. The majority of the 12th MSM Cavalry, including Flentge's company, was integrated into the 5th MSM Cavalry, with that regiment being moved out of SEMO into south central Missouri in February 1863.