We who believe the King James Bible to be the inerrant word of God do not place our trust in the King James translators. We do not defend their comments in the Preface, nor their theology, though I agree with much of it. We trust in God alone Who has fulfilled His promises to preserve His inspired words. He just happened to use the believing men of the 1611 Holy Bible as His instruments to continue this preservation.
They were not perfect nor without error in themselves. Just as God used Peter, though he denied the Lord and later separated himself from the Gentile believers and was to be blamed for his actions, (See Galatians 2:12-14) or Paul who was about to offer another blood sacrifice to appease the Jewish law-keepers in Acts 21:26, or John who twice fell down to worship an angel and was rebuked for it (See Rev. 19:10 and 22:8-9). God always uses imperfect vessels for His glory; if He didn't, nothing would ever get done.