All Jesuits are Catholic, including Pope Francis.
It is not possible to be a Jesuit and not a Catholic.
For individuals, it comes down to a matter of definitions, but to start out with Marquette, Marquette is an institution governed by a board of governors which includes six Jesuits and 26 laymen who are charged with, among other things, guarding the school’s Catholic identity. They include the head coach of the Clippers, who I some how doubt is Catholic. http://www.marquette.edu/leadership/trustees.php
Also included is Rev. Kevin F. O’Brien, S.J. , Vice President for Mission and Ministry, Georgetown University
When it comes to individuals, people who are excommunicated are Catholic in only a tengential sense. While the Church doesn’t have many declared excommunications, Canon Law still preserves the category of Latae Sententiae (automatic, undeclared) excommunications for, among other things, heresy and schism. While there are a number of ways to commit the crime and not incur the penalty, the two big ones are stupidity and ignorance, which is hard for Jesuits to pull off. Being excommunicated, latae sententiae or other wise, doesn’t automatically affect one’s relationship to an order.
It is true that it is not possible to start down the path of being a Jesuit without demonstrating some sort of connection to the Catholic Church, but after that, all bets are off.
I am sorry to say you are probably right. I used Pope Francis as an example because it is difficult to ascertain if he is a sincere Catholic.