Sally Celia Grogan was not the husband of Thomas Pinckney Grogan, Jr but of a Thomas Grogan that remained his whole life in North Carolina. I believe the Thomas Grogan she was wife of was the son of John Grogan but have never researched it.
Thomas Pinckney Grogan, Jr was only married once, and that was to Mary Kimble.
I have never found any data relating to a second marriage of Mary Kimble to a Mark Custer, Sr either. The last data I found on her was the 1860 Smyth Co, Virginia census.