Most Witnesses have enough cognitive dissonance to believe a proportion of good people who were never exposed to the truth will be saved.
They can't face the fact Watchtower has always maintained, with the exception of very young kids of baptised witnesses, only those baptised have the possibility of being saved. Most Witnesses will say even baptism is no guarantee. But of course that's not addressing the real question!
I'm sure a search of old publications will bring up plenty of quotes - try Avoidjw.org - and yes Antony Morris repeated that idea in a recent video.