Berlandier's diary (if you can find a translation) is fantastic first-hand history. He was with Teran when he returned to Fort St. Louis and destroyed it so completely that its location remained a mystery for almost two centuries.
You have Berlandier and Teran confused with the french deserter Jean Gery and the Spanish Governor Alonzo de Leon. Berlandier expedition w/Teran = 1835, Gery guides De Leon to the ruins of FSL in 1690.....
Berlandier's report; faunal, flora, and demographic has been translated to English. Smithsonian offered it back about 25 or so years ago.....