First, let's discuss search method. A reasoned pursuit of identity would explore all possibilities-- which we did -- and eliminate those less likely to be true. The second step proved to be source of contention.
Evelyn based her inquiry in part based on a hundred-year old letter to ADAH Director Thomas McAdory Owen about an Alabama command led by an officer named McDonald. The letter appeared in Dr. Owen's Coosa County file, hence the connection. That alone would allow us to eliminate out-of-state Confederate commands (but not Alabama companies serving in out-of-state regiments and battalions). At this point we should have focused on officers named McDonald who led Alabama mounted commands.
Certainly there are missing records in abundance, but relatively few message board searches end with that as the answer.
Here's what Evelyn wanted --
I would like a reference to Sherriff Young's memoirs and account of Confederate service.