For some reason, the War Department transcriptioners who took the raw hospital records and put them onto the individual cards recorded a large number of 1864 hospitalizations at the Episcopal Hospital, Williamsburg, which clearly was in error. Williamsburg had been under Federal occupation or was in between the lines since May 1862. I have seen them recorded for the Hampton Legion Mounted Infantry in 1864 in such fashion; the Legion was north of the James, and at that stage of the war I suspect that the actual place of hosptialization was Jackson Hospital, in northwest Richmond, where South Carolina casualties were treated.

My off-the-top-of-my head recollection is that the 23rd S.C. was engaged at Petersburg. I would guess that your man was either transported to Jackson Hospital in Richmond for treatment, oalong with other South Carolinians, or else the transcriptionist lumped hospitals at Petersburg under the misnomer Episcopal Hospital, Willaimsburg. One thing is certian -- he was not treated at Williamsburg.