Found a burial for Priscilla on Jerripedia 26 Apr 1741, (as Prisille) gives her maiden name as well and says wife of Richard
Good find. I have never researched in French-speaking countries before, so the name variants are new to me!
So you are descended from Catherine Le Cras, who was most likely baptised on 11 Mar 1711 in St Lawrence to father Richard. I see that her godparents were Mr. Elie Dumaresq and his wife.
The godparents of Richard Le Cras, baptised 4 Apr 1697 to a father Richard were also Mr. Elie Dumaresq and his wife, so I would say your theory is very plausible.
Are you looking to go back a generation to Catherine's parents? I imagine you have already traced all the godparents of Catherine's children (what a blessing to have godparents on baptism records, I must say!); I wonder whether it would be worth trying to trace all the godparents of Richard's children, including with his second wife? You never know what it might throw up.
Also probably worth tracing all the godparents of Richard and Catherine's siblings too; the ones I can see look like they are from very prominent and illustrious Jersey families. Maybe worth looking at their wills too?
You may have already done all this, but I thought I would mention it anyway.
Queenie