I always check the JPP names whenever I see an ex-slave who was born in Maryland or Virginia around the 1820's and lived in either Terrebonne or Iberville parish, LA.
[Also look for JPP records when looking for parents who were born in one of those states during that period].
This document had the signatures of some of South Louisiana's highest ranking (State and parish) officials.
(1) Henry Johnson (could it be the ex-governor?)
--- born in Virginia in 1779, he would have been familiar with the Jesuit Plantations. Henry S. Johnson was a memeber of the Territory of Orleans' government body. U.S. Senator, Representative and LA Governor (1823-1824). In 1825, he became joint owner in a Lafourche parish plantation, but it appears that he gave his residence as 'St. James Parish". He also had joint interest or sole ownership in properties across South Louisiana, including Iberville, St. Mary, and Pointe Coupee. He sold at least one property (along Bayou Lafourche) to Henry Schuyler Thibodeaux, another ex-governor of LA (though short-lived) and founder of Thibodeauxville.
Johnson retired to his plantation in Pointe Coupee parish (1850) after losing his last Congressional race ¹.
(2) H.M. Thibodeaux and H.C. Thibodeaux (signers)
They were the sons of Henry S. Thibodeaux. Could they have been in partnership with H. S. Johnson in the purchase?
(3) Dr. Jesse Batey
Another name that is linked with the Thibodeaux and Johnson families. He was one of the early settlers of Terrebonne parish.
¹ "Henry S. Johnson, 1779-1850." Encylopedia Louisiana. 17 Feb. 2006