This is not an answer, but it IS relevant as an examplt. Edward Porter Alexander, in his book, "Fighting for the Confederacy," tells of a situation during the battle of Chancellorsville, where in early evening he came across a Union Soldier lying by the roadside crying out loudly, "Water, Water, Water!" Alexander went to him and noticed the Union Soldier had been shot in the forehead and his brain was protruding. Alexander asked what state the Union soldier was from, and the soldier began shouting "New York, New York, New York," incessantly, as long as Alexander could hear as he rode away.
We must assume that this particular Union soldier died, but it would be likely that he was at least initially reported "missing."