3 Nephi 2:9
Accepting the Mantle
There is no record to tell us why he did not return but it is assumed that he was taken up or translated as believed for some other prophets in the past. We do know that Nephi gave the records to his son, Nephi to keep before he left.
I have also read speculation that maybe he went to Jerusalem and was one of the wisemen? The timing would be right but I personally doubt that he would have done that and left the country on a large voyage with no one knowing.
The plates of brass have been in the hands of the Nephite prophets for 600 years and they are still caring and protecting them and reading them and keeping more records as commanded.
3 Ne. 1:3 (2–3)
Alma 45:18 (18–19)
2 Kings 2:
11 And it came to pass, as they still went on, and talked, that, behold, there appeared a achariot of fire, and horses of fire, and parted them both asunder; and bElijah went up by a cwhirlwind into heaven.
Christ is the one who took him up. He has power of life and death and He could have saved himself from his executioners had he not chosen to allow them to crucify Him.
Jesus was taken up from the tomb.
Conference or manuals
Seminary manual Old Testament