“What we have is genuine God-breathed Scripture alone, preserved for this age and for ever.”
Well, except for the Books Martin Luther did not like, and the words that King James wanted changed. Sure.
While the King James is a good translation, much better than a translation of a translation into a coarse language, it like the DRB is uninspired. The texts of choice for the KJV are the ben Asher Hebrew OT and the NT Greek Byzantine/Majority textform known as the Textus Receptus, gathered by Erasmus. These are inspired Scripture. The Septuagint OT, including the other books, is not. Even Jerome rejected the LXX.
But this is not the issue. The issue is religion founded on something else beside Scripture as the guiding and deterministic influence.