Your answer is not entirely correct...\
Several Mormon apostles who were in a position of authority did absolutely teach that god had physical sex with Mary. Their statements have not been refuted by the LDS.
“The birth of the Savior was as natural as are the births of our children; it was the result of natural action. He partook of flesh and blood-—was begotten of his Father as we were of our fathers” (Journal of Discourses vol.8, p.115); and “when the Virgin Mary conceived the child Jesus, the Father had begotten him in his own likeness [flesh and blood]. He was not begotten by the Holy Ghost” (Journal of Discourses, vol.1, p.50).
Brigham Young insisted: “I will say that I was naturally begotten; so was my father, and also my Savior Jesus Christ...he is the first begotten of his father in the flesh, and there was nothing unnatural about it” (Journal of Discourses vol.8, p.211); “Now remember from this time forth, and for ever, that Jesus Christ was not begotten by the Holy Ghost” (Journal of Discourses, vol.1, p.51).
Orson Pratt (LDS apostle) taught: “the Father and Mother of Jesus, according to the flesh, must have been associated together in the capacity of Husband and Wife…as God was the first husband to her, it may be that He only gave her to be the wife of Joseph while in this mortal state, and that He intended after the resurrection to again take her as one of his own wives to raise up immortal spirits in eternity” (The Seer. p.158, 1853).
Joseph Fielding Smith wrote: “The birth of the Savior was a natural occurrence unattended by any degree of mysticism, and the Father God was the literal parent of Jesus in the flesh as well as in the spirit” (Religious Truths Defined, p.44).
“Christ was begotten by an Immortal Father in the same way that mortal men are begotten by mortal fathers” (Mormon Doctrine, p. 547, 1979).
I love it when LDS think they know more than their prophets.