Well, OP is confused. There are of course some differences between the MT and the Dead Sea Scrolls in Daniel, but they are very minor [0], to the extent that i

Well, OP is confused. There are of course some differences between the MT and the Dead Sea Scrolls in Daniel, but they are very minor [0], to the extent that in many cases the MT actually harmonizes better with the scrolls than they do with each other. What OP may be referencing are the much more significant variations between the MT and the LXX. The LXX version of Daniel is quite a lot longer, uses very different details, and even includes additional stories [1] not present in the MT. This has presented something of a problem, since although the LXX is a translation of a source text and so is inherently inferior to it (like any English translation would be), it is a translation so incredibly old that the later parts of the bible use it when they quote the earlier parts, and it was the standard version in the ancient world for quite some time. Meanwhile, the MT is an actual manuscript in the source language but arrives at least a thousand years later on. This creates a bit of a puzzler about which one to follow when they are quite different, and they are quite different in Daniel. The DSS basically settled the issue with regards to Daniel in favor of the MT and against the LXX. There was not really anything "new" that we did not have in the MT, but there were some LXXisms that fell out of favor. However, in other books it went the other way, sometimes favoring the LXX reading. This suggests that the LXX and the MT may reflect different underlying source texts, that are both quite old and both have some legitimate claim to being authoritative. The situation is complicated somewhat because most of these books are more compilations than they are a work by a single author, and deciding where the original work ends and the interpolations begin is pretty arbitrary. [0] https://books.google.com/books?id=6f9-Fnmy3sEC&pg=PA149&lpg=PA149&dq=daniel+qumran+mt&source=bl&ots=0Wt4J5iP-D&sig=bwf9xcSxmfK2cQwyMI95yjd1QZg&hl=en&sa=X&ved=0ahUKEwjekvLzltPPAhUV84MKHQksCsMQ6AEIRzAG#v=onepage&q=daniel%20qumran%20mt&f=false https://books.google.com/books?id=6f9-Fnmy3sEC&pg=PA149&lpg=... [1] https://en.wikipedia.org/wiki/Bel_and_the_Dragon https://en.wikipedia.org/wiki/Bel_and_the_Dragon