Hello Mike. Thanks for the information. Yes, Uncle Crockett Boone wasn't ready to give up the fight. According to his obituary, "after the Star of the Confederacy had set, he went with several other Confederate soldiers to Mexico to cast his lot with Prince Maximillian." I have come to believe that perhaps he joined the Shelby Expedition, then later returned in October to get his parole certificate at San Antonio.
To answer your question about who signed his parole certificate in San Antonio, the two names are Wesley Merrett; and one I can't quite read, but it looks like F. Poe Keane, captain of the 18th New York Calvary, provost marshall general. Does that tell us anything?