I received some insight into two prophets mentioned in the Book of Mormon that are not mentioned in the Bible while reading 3 Nephi 10:16.: "...because they testified particularly of us, who are a remnant of their seed."
These prophets were perhaps not recorded in the Bible, the record of the Jews, because they were of the house of Joseph. Their prophecies may only have been recorded in the Plates of Laban which was the record of the house of Joseph.