Bill is going to have his work cut out for him, sorting this out.

According to the regimental muster roll, Colonel Geoghegan was left in charge of the sick at Camp Hope (having been sick himself for some time) when the regiment began its march to western Arkansas, and did not rejoin the regiment before resigning due to ill health on December 18, 1862.

On the other hand, Columbus Gray would presumably have known his lieutenant-colonel on sight if he had seen him on the field.

The ball's in your corner, Bill.