Yeah...they're Sisters alright.
- - - Updated - - -
I got an idea: What if the Sepulcher Zovaal is looking for is on Azeroth's Moon? Could not be, but still...
Would make a LOT of sense imo.
- - - Updated - - -
That way, the Pantheon of Life, Elune, etc can all be introduced with the Moon, Reality's invasion from the Jailer, and the Gardens of Life being the central parts of it all.