Those earlier English Bibles are part of the same preserved stream. The KJV is one that stands within that stream as its mature culmination.
It has not been proven that the KJV has a better and more accurate rendering of every original-language word of Scripture in the preserved stream than any one of the pre-1611 English Bibles.
In at least some places, another pre-1611 English Bible may have a clearer, better, or more accurate rendering than the KJV has when compared to the same preserved Scripture texts. One clear evidence of this is the fact that some renderings in the original 1611 KJV edition were later changed or corrected to match renderings already found in an earlier pre-1611 English Bible.
The KJV translators left uncorrected the error of the name of the wrong group of people “Amorites” (1 Kings 11:5) that is in the 1602 edition of the Bishops’ Bible, which could make them responsible for this error of fact being found in the 1611. At 2 Kings 24:19, the 1611 edition has the name of the wrong king “Jehoiachin,” introduced from the 1602 edition’s “Joachin.” If the KJV translators had noticed this error of fact at 2 King 24:19 in the 1602 edition of the Bishops’ Bible, they failed to make sure that the printers at London corrected it since it remained in editions of the KJV printed at London in 1613, 1614, 1616, 1617, 1626, 1630, 1631, 1633, 1634, 1640, 1644, 1650, 1652, 1655, 1657, and 1698. The 1560 Geneva Bible already had the correct rendering at these two verses, and later KJV editions were later corrected to match that correct, accurate rendering of the Geneva Bible.