Deuteronomy and the Book of the Law in Second Kings 22 to 23

There is an agreed upon connection among biblical scholars between the authorship of this Deuteronomistic history and the book of Deuteronomy. In second Kings, we read about the King Josiah who is the only King in first and second Kings who gets an A plus rating. It's a clue that Deuteronomy is a seventh century law code under during the reign of Josiah. And many scholars think that this book of the law, it's not Torah as a whole. It's not Genesis through Deuteronomy but at least some early version of it.