Or it's just Merithra's attempt to side-step having to lead and it just fails, or it's reincarnation instead of resurrection and brings her back as a whelp, or she's being turned into a pseudo-Loa, spirit-like entity a la Bwonsamdi and Vol'jin, or it means "prepare the way for her" in the less direct sense of "prepare the way for Ysera (so that she can send the Night Elf souls into the new world tree).
Who knows.