You got it wrong.
Starcon does not know the identity of this entity that dumps toxic waste on planets, so they coined the term "Sludge Bandits" to describe that mysterious entity, which happen to be Quirk. Genetix had a warehouse of useless goop and bribed Quirk to get rid of it. There is no mysterious organization dumping waste on planets, it was Quirk all along. And before you mention it, that brown alien in the intercepted transmission is no bandit, he works for Genetix, try visiting it at the start of the game (the coordinate are always the same.)
Or they beamed on their ship and left. Never to be seen again.
The Goliath was attacked by the mutated colonists. If you contact Starcon before beaming on Klorox 2, Quirk says he's busy with a shuttle rescue mission, and in the logs on Klorox 2 you discover that the mutants headed for their shuttle when they were done infecting the colony.
Quirk is dead. There are no bandits. All mutants got aboard the Goliath and were cured. The only remaining threat is Primordial Soup canisters dumped in space or inhabited planets, awaiting to be discovered.
Virus and parasites tend to do that to their host.
It means he's dead, until someone use magic to resurrect him, like it stupidly happens all the time in comics, cartoons and video games.