The Surrender in May of 1865 was general surrender. Some units sent in the paper work, got their paroles and went home. Others were interviewed. Some units burned their records and went home. My GGH said he lived in Athens, TX in his parole and I can find no record of him ever being there. On his release he was probably in or near Winona, MS and he married and settled down there. He never returned to Texas, though he did put in a pension request 20 days before he died and it was approved the day after he died in Ocala Florida. It was the one document that allowed me to find him and his brother and then back track him to Tennessee.
The Department of the Army did the record development, I understand. Others here at the Texas site probably have more knowledge of how. I did read a little about it at the National Records web site. The process of record development was a serious indeavor much like the census. They had all the records and used interviews and reconstruction to make the records good. I am sure they also used state and county records. Specific orders found on file were entered in a soldiers records. My GGF was trandferred from Company K of the 6th to Company I. That transfer was in his files, as were assignments for specific duties. Interviews were probably with old first sergeants and adjutants. These were the guys familar with the rosters.
The records of parole in May 1865 were the best possible with the situation. Thousands of troops heading in all directions, with limited transportation. Many just walked. Others used the river boats and did not have to pay. Though I can not imagine going down the Mississippi and then up the Red to Texas. Even the Union did not have the capability to keep every thing in hand. Some arriving at the depot in east Texas received new rifles that they were giving away. Along with the Southerners going home were the Union prisoners heading north and the Union Army moving in. Some Southern soldiers were killed by Union soldiers that had not heard the war was over. Others were killed by bandits. Colonel Dudley Jones of the 9th took his unit back as a large company. Others went back in small groups.
The Parole record you have may have been one issued in May of 1865 by a US Governemnt representative. In some places these documents were necessary to live because of reconstruction. The Pension Request and approval were done at the County level by the County Judges and court. These were official court documents and most states still provide certified copies.
The Reorganization in May 1862 was directed by the Confederate Government and War Department. It was done to insure organization according to specific structures. Age limits were established and the young and old were sent home. Leadership was improved. The units got rid of those it did not want. Some officers went home for cause. Colonel Lane went home because he would not lead Infantry.
A lot of the men on the muster rosters and parole registers never made it home. They had already left their units and were home by the surrender. Others like my GGF and his brother just milted into the local vacinity. They were on the roster, even though my GGUncle was Absent and I have not found anything on that. His brother may have covered for him. With the units of the brigade we know that almost half had received furlows and were home or on the way when the war was over. Sul Ross just stayed home.
Some of my answers are general in nature and are ment to allow you to see how your kin fir in. We have nothing that says that he was released in 64, but we do in 63 and 65. Here an educated guess says he was released or escaped, because he had a parole in 65. His records would state what prison he was released and when. The general unit parole from Cintroelle, Al was Army wide in the Trans-Mississippi Department. It was not for prison camps. Their paroles were separate. I think your kin was back with his unit. Did he go back to Texas? Were their ties or was his love of the Tenessee that he had fought it pull him? I would bet on friends he made or a gal he met.
This is enough. We almost have a book.