Do I remember right? The Dead Sea scrolls were a major link in proving Daniel's book was prophetic. Babylon was still not completely abandoned in 150BC when the Qumran community copied parts of Daniel's book, containing the prophecy about Babylon's completet desolation.
The JWs only read WT approved materials, anything else religious is from apostates. Which always made me wonder, because the WT constantly quotes from all kinds of books. "Study" is a strong word, but I think at least some in writing department must have read heretic writings too.