https://forgottenrealms.fandom.com/wiki/Skull_of_the_Void The Mindflayers from the Skull of the Void are known for their ability to levitate, an ability granted by eating a lot of Beholder brains. The Mindlayers in BG3 are seen levitating, perhaps showing a link to the Skull of the Void, Mindflayers as well. It makes sense that there would be a connection between the Mindflayers of the, Shull of the Void and Glyth. Both are in realmspace.
