You'll have a better idea as to what was happening with these people than I will.
The soldier's name was taken from the May 1865 record of events for Co. D, 1st Florida (U.S.) Cavalry Regt. Since no description accompanied the report of his death, it may be that Peacock died in what we might term an "incident". Could be that he was found dead outside camp. It's hard for me to imagine some kind of actual encounter between organized military commands at this late date.