Here you go, again from Booth's, which has good but not always complete information. Interesting that they were prisoners for almost 2 years!! Would have figured that they may have been exchanged earlier.
JIM T

Chafin, W. L., Pvt. 8th La. ____ Co. H. Federal Rolls of Prisoners of War, Captured Gettysburg, Pa., July 4th, 1863. Forwd. to Fort Delaware, Del. Paroled and transfd. to City Point, Va., for exchange, March 7th, 1865.

Oliver, W. A., 1st Lt. Co. H, 8th La. _. On Federal Rolls of Prisoners of War, Captured. Recd. at Pt. Lookout, Md., June 25, 1864, from Ft. Delaware. Paroled and Transfd. to City Pt., Va., and exchanged. March 7, 1865