If they profess it in ignorance they can be saved
Major - All men have an obligation to serve God, which is why they were created and the only way they can get to heaven.
Minor 1 - There is only one way to serve God, which is in His Catholic religion.
Minor 2 - As Scripture teaches: God wills that all men be saved and to come to the knowledge of the Truth.
Minor 3 - There is only one Truth, which is contained in the Catholic religion only and completely.
Conclusion - If a man dies not knowing of the Catholic Faith then he has only himself to blame for his ignorance and this ignorance is sinful and damning, because all men have an obligation to seek God and His Truths, which God will provide and enlighten as He has infallibly promised.
All those who know of the Catholic Faith, yet cling to error and false religions, are also ignorant due to their sinful omission and sinful sloth, since God desires all men to be saved and provides billions of actual graces to every man during his lifetime for the purpose of his salvation.
There is no such thing as invincible ignorance or excusable ignorance. All men who aren’t Catholic aren’t so of their own choosing. All men who are in hell (Catholic and non Catholic) are there of their own choosing.