I tried to find something on Southwest Louisiana Records CD 1750-1900 and found the children's records, but unfortunately paternal and maternal grandparents aren't named in their specific records:
BELL, Olivier (Thomas & Arsene GRANGER) b. 8 Oct. 1852 (Opel. Ch.: v.4, p.406)
BELL, Olivert (Thomas & Arsene GRANGER) b. 24 April 1856 (VP Ch.: v. 1, p. 125)
BELL, Thomas (Thomas & Arsene GRANGER) b. 22 July 1859 (Opel. Ch.: v. 6, p. 141)
BELL, Celimene (Thomas & Arsene GRANGER) b. 28 Jan. 1861 (Opel. Ch.: v. 6, p. 141)
This could be your Thomas:
BELL, Thomas d. 23 Sept. 1870 at age 60 yrs. (Arnaudville Ch.: v. 1, p. 6)
The only Granger born in 1822 was
GRANGER, Cleonide (Charles & Suzane GRANGE) b. 9 May 1822, bt. 16 June 1822 Spons: Fabien LANDRY & Lise MIRE. Fr. Michel Bernard BARRIERE (Laf. Ch.: v.1, p.4)
The name Bell alone was in 777 records...I went through over 200 of them, and I did go through all that had both Bell and Thomas or Bell and Granger.
There was another Thomas Bell, who married Agathe Hayes in 1828... of course that can't be the same one if he was born in 1816. Plus it looks like he died in 1838. It's possible that he was the father of your Thomas and Thomas' mother died so he remarried. In any case, he was the son of a Jean or Samuel according to his records.
BELL, Thomas (Samuel) m. 7 Jan. 1828 Agathe HAYES (Frank. Ct.Hse.: Mar.#404)
BELL, John (Thomas & Agathe HAYSE) b. 18 Aug. 1835, bt. 14 Sept. 1835 Pats: Jean BELL & Marie PAGET; Mats: Michel HAYSE & Rosalie DEROUEN; Spons: Jacques DEROUEN & Rosalie DEROUEN. Fr. Marcel BORELLA (SM Ch.: v.8, #925)