First and most importantly, no Bible translation is error free. If it has one error, it is not the word of YAHVAH, period.
The Dead Sea Scrolls,(DSS): Some scholars believe that the religious sect called the Esseens, were responsible for these manuscripts,(MSS). They also believe that they were heretics because of some of their beliefs.
They copied these DSS from a more ancient source, so these scholars say. Since we have them today, a few things are actually known about them. 1: They are in Hebrew, and, 2: they were copied from older versions. It is also believed that they are 1000 years older than MSS that were known about before 1947 A.D.
Seeing that this is the case, really, very little is known about them. One thing is for sure, the people (men,women, children?) who wrote them were gone from this community by 72 A.D. This means that the scrolls were placed in the caves before then. Could they have been placed in the caves after 72 A.D.? Yes.
If this was the case, it would mean that they left the area with their scrolls, and when the Roman army left, they came back and later hid the MSS. I see this as very doubtful. Jerusalem, being only 15 miles from these caves, was completely destroyed. The Romans turned Israel on its head from north to south, and the Qumran community was not immune.
These people were either killed, taken prisoner, or sent somewhere else. Their MSS stayed in those caves for nearly 1,880 years without being disturbed. There is nothing written about them before 1947 A.D. because nobody knew they existed.