In MY humble opinion, I think you are correct about the spelling of MONTESSON and FRIN. I looked for FRIN on Geneanet, but there are so many, I need to find some additional information to help narrow it down. Geneaology could become a full time occupation! So many things to explore!
I will definitely look further with the spellings you gave me.
I am curious, too, about MONTESSON. The grandson of Pierre Boudet, Pedro Jacinto Boudet, presented papers from Rochefort to the town council of Santiago de Cuba in 1789 saying he was from a noble family. Those papers could give me several generations.Unfortunately trying to find those papers in Cuba has resulted in a dead end. I'm wondering of the 'nobility' connection came through MONTESSON rather than BOUDET, although there are titled Boudets here and there. (Boudet is much more common name than I thought it would be!) I found that there was a Chateau de Montesson with marquis in Bais, département de la Mayenne. But at this point it is just a note to myself to explore further. It might not be related.
There is also a town of Montesson in the Yvelines department in the Île-de-France region in the suburbs of Paris. In the marriage record of BOUDET and MONTESSON, it seems to mention something about one or both of Genevieve's parents from the "ville de Paris".
I also had a note to explore the birth record of Marie Boudet and I think she could be a daughter of Pierre and Genevieve. Her name has appeared a few times when I was searching for other names. Now, with the information you provided, she is next on my list to check. It would make sense that CHEVILLARD DE MONTESSON, a ship captain, would be connected to the BOUDETS that were involved in trade with the colonies.
I cannot thank you enough for your time and effort and looking for information. Do you have relatives in the Fallourd or Boudet families?