OK, I've spent enough time on this to conclude I will not be able to arrive at anything conclusive. In short, there were decades of civil-war-level tensions dividing the traditionalists and the so-called Hellenists. Antiochus intervened and enforced repressive actions against those who resisted, and the temple was center of all this. The post by Kaleb endorsed the position that the Hasmonean powers themselves created the book of Daniel as well as a subsequent (~25 yrs. later) work, 1 Maccabees, that endorses Daniel as a 'prophet' and quotes from the book. I keep coming back to that idea and really find it attractive. I'm only now adding they must have used previously existing tradition/folklore for the framework and for added credibility. I'm always puzzled by would-be prophets' willingness to make short sighted predictions, but it's a record that continues to this day so my objection to official Hasmonean scribes being responsible for it cannot be justified. It's also hard to distinguish genuine zealotry from manipulative propaganda, so can't say which motivation was involved.
For me this explains the acceptance of Daniel by opponents of the Maccabean 'wicked priest' who gathered at Qumran, in that the book of Daniel was obviously 'unsealed' prior to the death of Antiochus (prediction of death wrong as well as the predicted glorification of holy ones to occur subsequently) and endorsed by priests and others prior to the gradual increasing corruption of the priesthood.1 Macc. parallels the courage and zealous violence of Judas Maccabees to Phineas of Numbers 25 wherein Phineas is rewarded with the high Priesthood. This then justifies his taking the High Priesthood and the gradual replacement of priests with those who endorsed him. This replacement of priests apparently resulted in the ousting of the TofR, (as suggested by terminology used of him and their opponents) who then either formed or joined to lead the pietists cult at Qumran where he was regarded as the inspired "interpreter of the Law". Michael Wise suggests he was the missing High Priest of the 160's, who knows. In the end the members of Qumran came to see the "smoke of the alter as a stench to God's nostrils".
The Community Rule and Damascus doc, (Qumran) refers to 20 years they were aimless until the leadership of TofR and that he arrived 390 years since God “gave them into the hand of Nebuchadnezzar, King of Babylon”. A number of scholars have posited these fragments a part of a schematic reinterpretation of Ezek 4 and the Daniel 70 weeks schema. (390+20+40+40=490) If so, this would explain the apparent adoration of the book of Daniel and related Daniel traditions. They had lived through the disappointment of the intended 'end time" and had of necessity accepted a reapplication of the passages featuring the TofR so that 50 or more years they could still regard themselves as the "last generations".
So, I'm growing warmer to the idea that the book of Daniel was the work of associates of the Maccabean clan prior to the death of Antiochus who had high apocalyptic expectations and was after just a couple decades reinterpreted through the person of the TofR after his purge from the Jerusalem priesthood. How much the TofR was involved in the original work is unknown but the reinterpretation revolving around him seems consistent with his role as "interpreter". It remains possible that the TofR was initially convinced the cause and actions of the Maccabees was providential but when disillusioned and eventually booted he assumed a role as cult leader able to uniquely understand the new book of Daniel and the rest of the sacred writings.