The following is what is found in the American Civil War Research Database. There is no record of him found in the 4th Georgia.
There is in his CSR files, correspondence from the War Department to the Georgia State Pension Commissioners dated November 30, 1915. This would suggest a Confederate Widow's pension application.

George Martin

Robert H. Carson

Residence Macon County GA;
Enlisted on 4/1/1864 as a Private.

On 4/1/1864 he mustered into "C" Co. GA 12th Infantry
He was transferred out (date not stated)
(Transferred in 1864)

He was listed as:
* Detailed (date and place not stated) (Courier for Gen. Cook, in 1864)
* Wounded 5/6/1864 Wilderness, VA

He also had service in:
"I" Co. GA 4th Infantry

(Buried in Carson Cemetery, Macon, GA.)

Sources used by Historical Data Systems, Inc.:

- Roster of Confederate Soldiers of Georgia 1861-1865