If you put stock in the hyperbolic orbiters systems, a good-fit line through them generally hits the center of the bubble with the Anomaly.

Pink = Hyperbolic Orbiter systems, Green = Thargoid sites in the Pleaides, Blue = Guardian Sites, Yellow = reference systems, Grey = systems I have been

EDIT WITH TINFOIL HAT THEORY: "Hyperbolic Orbiters" are an orbital mechanics thing that was put in the game to possibly model the flight of objects like comets with crazy-eccentric, far-out orbits and are made to show background things a cmdr typically isn't supposed to be able to fly to. Maybe Frontier is using these things to path the graphics for the Anomaly and this might explain why some people have seen apparent retrograde movement when observing over time?

Possible route of the Anomaly

Video showing 3D better