This is all very easy to clear up…
If this statement is true (which it is)
“We declare, say, define, and pronounce that it is absolutely necessary for the salvation of every human creature to be subject to the Roman Pontiff.” Pope Boniface VIII, Unam Sanctam
and a person becomes subject to the Pope through sacramental Baptism
“The Church exercises jurisdiction over nobody who has not previously entered the Church through the gates of Baptism” Council of Trent, Doctrine on the Sacrament of Penance (Session XIV), chapter 2
Then it is clear that a person must at least be a baptized member of the Catholic Church to be saved.
(They must also be a Catholic who dies in a state of grace, etc.)
“The most Holy Roman Church firmly believes, professes and preaches that none of those existing outside the Catholic Church, not only pagans, but also Jews and heretics and schismatics, can have a share in life eternal; but that they will go into the eternal fire which was prepared for the devil and his angels, unless before death they are joined with Her; and that so important is the unity of this ecclesiastical body that only those remaining within this unity can profit by the sacraments of the Church unto salvation, and they alone can receive an eternal recompense for their fasts, their almsgivings, their other works of Christian piety and the duties of a Christian soldier. No one, let his almsgiving be as great as it may, no one, even if he pour out his blood for the Name of Christ, can be saved, unless he remain within the bosom and the unity of the Catholic Church.” Pope Eugene IV, Cantate Domino