Mormon 8:10

and there are none that do know the true God, save it be the disciples of Jesus, which did tarry in the land until the wickedness of the people were so great, that the Lord would not suffer them to remain with the people; and whether they be upon the face of the land, no man knoweth.

No one knows the true God except for the followers of Jesus. They stayed in the land until the people became so wicked that the Lord would not let them stay with the people anymore. No one knows if they are still on the land.

No one knows the true God except the disciples of Jesus, who stayed here until the people became so wicked that the Lord wouldn’t let them remain. Whether they’re still alive somewhere, no one knows.