I have the same gg grandparents the information I have is that the father of Veronique was Belomine Major b. 1780 his father WAS Etienne Major b.1746, d.1822 here's where it gets dicy-Etienne's father was Guillaume Bosseron/Bouton married to Catherine Cheval. Supposedly he was a French Major thus the use of the name Major was introduced.
You are correct Hortense and Veronique were 1st cousins both namde Major. Hortense's father was Pierre Vallery Major.
You may already have this information since you posted years ago, if not I hope it solves some misteries for you.