What of the Catholic who, raised and taught by a bunch of Catholics, never hears about the tribesman's true religion.
Does the Catholic fall back in the tribeman's caste system or get damned to the tribesman's hell?

OF COURSE NOT!

How could God damn you for having parents raised to believe in, and therefore teach you, one of the thousands of non-Christian religions?

Or how could God damn you for realizing that there are thousands of equally baseless religions, and that in choosing any one religion you are being damned by ninety-nine-hundred-ninety-nine other religions?

How could God put every person's immortal soul up for a one in one-thousand chance bet on whether they happen to pick that one true religion?

Answer: He couldn't!

and if he could, he sure as hell wouldn't deserve worshipping!