Was William Blalock imprisoned?

There are a half dozen people from the 1860s whom I have spent a great deal of time researching: Lawrence O'Bryan Branch, James H. Lane, John B. Palmer, Collett Leventhorpe, Richmond M. Pearson, and..... William M. Blalock. I'm not sure why I'm so drawn to the story of Blalock. There are a great many details that we just simply don't know about his life.

This evening, while reading through his pension application, I came across an interesting turn of phrase. In this affidavit, dated November 1874, Blalock states that he was "arrested by Maj. Harvey Binghams command[, had his] hands tied behind him, and sent to head Quarters in Watauga Co., N.C. and there put in the Guard House for a term of 8 days, and on the 9th day took said affiant [Blalock] out of guard house, tied his hands behind him and started with him to Castle Thunder, to wear the "Ball and Chain." Blalock later claims to have escaped.

When doing research for the Grandfather Mountain book (2014), I came across this anonymous riff:

     I'd ruther be on the Grandfather Mountain

          A-taking the snow and rain

     Than to be in Castle Thunder

         A-wearin' the ball and chain.

The late Frances Casstevens, in her book George W. Alexander and Castle Thunder, stated that it was a popular ballad of the time period. I have found the quotation in many other places, like Radley's Rebel Watchdog and Thomas's The Confederate States of Richmond: A Biography of the Capital. The fragment appears in 1952 in one of Frank Brown's Collection of North Carolina Folklore  and in 1951 in the Southern Folklore Quarterly in 1951 (volume 199). On an online search, I don't see it prior to 1951.

How many people, in the 1860s, actually knew of Grandfather Mountain? Probably just a handful. Was the phrase popular enough to be used in Blalock's Pension application? I wonder if he ever made it to Castle Thunder? Do the Castle Thunder records survive? (It appears that they do, at the National Archives.) Just something to ponder.