Kathy -

Sadly this is true of the great majority of all wartime Confederate burials. Markers for nearly all graves during the war were simply wooden slats. Some people were careful to scratch a name, unit and date; others were not.

The McGavock cemetery at Franklin provides a good example of what happened to wartime Confederate dead. After the battle, soldiers and residents buried the dead and gave them wooden markers. However, shortly after the war, poor people began using the wooden markers for kindling in cold weather. Others began to decay and wear in the weather.

Hearing of this, the MacGavock family had all known burials exhumed and moved to Carnton, just south of town. The people of Franklin and other patrons paid for inscribed stone markers. Without this unusual intervention, wooden markers wouldn't have lasted for long.
http://www.mcgavockcemetery.org/

Coming home by rail this man almost certainly passed through Selma. If too sick to travel further, it's possible that he might have been admitted to a Selma hospital for treatment. Hospital admissions sometimes made local newspapers. Selma newspapers for the second half of 1864 are difficult to locate, but you can check ADAH holdings.