The trip to the Elementus Domain from the edge of the Nine Worlds Domain was a long, arduous journey through the Dark Void. While the option to use a Void Gate to travel was there, the price was disgustingly obscene. Due to the Mystic Radiance Belt, the fixed space was infused with a mystic power, strengthening it in every aspect.
The function of Void Gates was to establish a tunnel between the folds of fixed space, exiting out at a certain set coordinates, establishing a stable connection between two points in space. This was why Void Gates were affixed to certain locations as well, requiring an extremely powerful and stable foundation to pierce through fixed space, creating the tunnel and connection.