The Hoopy Casino ship/station will hyperspace if its energy gets low, so I've seen the same behavior many years ago.
The "killing effect" of a very large wormhole is caused by any large ship/station/asteroid that gets sucked in -- you crash into those at the wormhole destination typically before you even get to see the new system.
I've since experimented with how big a wormhole cloud can be...and I hit a size so big the game no longer displayed it from any distance.
This one is smaller than that...
The targeted wormhole is a quickly-decaying one from a small jump-capable device/ship.
The multiple wormholes in the distance were mostly made from the killer asteroid in Asteroid Storm, so they're much bigger than they appear.
The asteroids are cinder asteroids in the core game, seen in a post-nova system.
However the thing-of-note is what dominates the picture and is further away than all the other stuff.