The former provinces of Champagne, Bourgogne and Franche-Comté put together would form a really huge territory. And Franche-Comté only became part of France in 1678. But yes, there are Saint-Pierre churches in Franche-Comté, some very famous.
The Cercle Généalogie du 52 has a handy research tool - you can try it and see the results for the name Amiot. I had no luck with a burial for either of Jeanne's parents, but the possibilities are so numerous, it's a bit like looking for a needle in a haystack.
Still. I would narrow it down to the current departements of Haute-Marne (perhaps not the North of it), Côte-d'Or and part of Aube.
Well, that was a bust, the notarial acts are now online for Romain Becquet, found hers, says exactly the same thing, parish of St-Pierre, diocese of Langres.