I'm a Minimalist. I've corresponded with Russell Gmirkin on much of this material a few years ago. He dates this to 273-269bce. I go further and follow Dr. Robert m price and Philippe Wajdenbaum placing the Deuteronomist code in the second century bce under the Hasmoneans.
Three layers I think is right for kings. Imo the story originally ended at jeroboam ii. The rest was added later using Berossus for the hezekiah and Babylonian exile material and the kings from uzziah to Zedikiah. But as mentioned before someone added Josiahs death.
Have you read Margret barker works? The priesthood split in 155bce between the Zadoks and the Hasmoneans