This is outside of my area of knowledge, but I feel compelled to speak up in order to render aid. I looked for a Colonel Birge as head of a Confederate regiment and found none, unless I missed something. There was a Colonel John W. Birge who was regimental commander of Birge's Sharpshooters, a Union unit. Perhaps you could research this a bit to see if Birge had a Captain Wilson who commanded a company in his regiment. If not, well, maybe I erred and should have remained quiet.

Bruce Nichols