They murdered many more people than just Monarchs:
Foxe's Book of Martyrs : John Foxe https://archive.org/details/ActsAndMonumentsJohnFoxe
The Jesuits' restoration under Pius VII (1814) was regarded as their divine vindication
No it was regarded as a result of their poisoning Pope Clement.
The Catholic Church recognizes true martyrdom as faithful witness to Christ (CCC 2474). Alban Butler's 'Lives of the Saints' provides verified accounts of Catholic martyrs (including under Protestant regimes). The Church views Foxe's accounts as propagandistic, highly partisan, and points to its reliance on unverified eyewitnesses and document mutilation. That propaganda book was especially used in England. In the middle ages monarchs used religion for their politics.
https://www.youtube.com/watch?v=nqIQZYLrpkE Foxes Book of Martyrs
The last Pope to bear the name Clement was Pope Clement XIV, who died in 1774, and if Jesuits' were restored in 1814 you have no connection to a non-verified (rumor) poisoning and their restoration. It looks like there were six popes after Clement to the date of the restoration.