As a person who was once LDS, I will try to explain it.
Mormons believe in three levels of heaven. ALL people (universal salvation) get to one of the levels. There are required ordinances that one must perform in order to move to a higher Kingdoms. Without a Mormon baptism, one is relegated to the lower kingdom, never having a chance to dwell with God in the highest Kingdom or Christ who is a separate personage.
What the Mormons do is what the Mormons do, they perform a valuable service by preserving these records and they do it for NADA.
Heaven is Divided Into Two Kingdoms.
20. As there are infinite varieties in heaven, and no one society nor any one angel is exactly like any other [4.1], there are in heaven general, specific, and particular divisions. The general division is into two kingdoms, the specific into three heavens, and the particular into innumerable societies. Each of these will be treated of in what follows. The general division is said to be into kingdoms, because heaven is called the kingdom of God.
21. There are angels that receive more interiorly the Divine that goes forth from the Lord, and others that receive it less interiorly; the former are called celestial angels, and the latter spiritual angels. Because of this difference heaven is divided into two kingdoms, one called the Celestial Kingdom, the other the Spiritual Kingdom [4.2].
22. As the angels that constitute the celestial kingdom receive the Divine of the Lord more interiorly they are called interior and also higher angels; and for the same reason the heavens that they constitute are called interior and higher heavens [4.3]. They are called higher and lower, because these terms designate what is interior and what is exterior [4.4].
23. The love in which those are, who are in the celestial kingdom is called celestial love, and the love in which those are who are in the spiritual kingdom is called spiritual love. Celestial love is love to the Lord, and spiritual love is love towards the neighbor. And as all good pertains to love (for good to any one is what he loves) the good also of the other kingdom is called celestial, and the good of the other spiritual. Evidently, then, the two kingdoms are distinguished from each other in the same way as good of love to the Lord is distinguished from good of love towards the neighbor [4.5]. And as the good of love to the Lord is an interior good, and that love is interior love, so the celestial angels are interior angels, and are called higher angels.
24. The celestial kingdom is called also the Lords priestly kingdom, and in the Word His dwelling-place; while the spiritual kingdom is called His royal kingdom, and in the Word His throne. And from the celestial Divine the Lord in the world was called Jesus, while from the spiritual Divine He was called Christ.
25. The angels in the Lords celestial kingdom, from their more interior reception of the Divine of the Lord, far excel in wisdom and glory the angels that are in His spiritual kingdom; for they are in love to the Lord, and consequently are nearer and more closely conjoined to Him [4.6]. These angels are such because they have received and continue to receive Divine truths at once in their life, and not first in memory and thought, as the spiritual angels do. Consequently they have Divine truths written in their hearts, and they perceive them, and as it were see them, in themselves; nor do they ever reason about them whether they are true or not [4.7]. They are such as are described in Jeremiah:-
This guy died in 1772.