score:3
First off, you are correct. The Journal of Discourses is not canonized scripture and not considered doctrine:
The Journal of Discourses is not an official publication of The Church of Jesus Christ of Latter-day Saints. It is a compilation of sermons and other materials from the early years of the Church, which were transcribed and then published. It included some doctrinal instruction but also practical teaching, some of which is speculative in nature and some of which is only of historical interest.
Answer 1: Absolutely not. We believe the Biblical Account.
Answer 2: Irrelevant because the LDS church does not teach that.
Side note: Yes, the church does teach Adam is Michael the archangel, great job with a source directly from LDS.org.
Upvote:7
No, Mormons do not believe that.
The doctrine was never submitted to the councils of the Priesthood nor to the church for approval or ratification, and was never formally or otherwise accepted by the church. It is therefore in no sense binding upon the Church. Brigham Young's "bare mention" was "without indubitable evidence and authority being given of its truth." Only the scripture, the "accepted word of God," is the Church's standard.
βJoseph F. Smith, letter to A. Saxey, January 7, 1897, HDC.
The best we can figure, as far as I know, is that Brigham Young was misquoted or, at least, it was entirely his opinion. Today the LDS Church refutes it as false doctrine.