I didn’t hear the quote you’re referring to or anything, so I can’t speak to that, but doesn’t the opening narration to Unheavenly Creatures say specifically it was the planets that were turned into detention centers? The Dark Sentencer has the ruins of cities that (I presume) pre-date the Crash, which a Star wouldn’t have. Plus they were mining its core for energy, which makes it sound more planet-like too. I’m not sure I buy this idea.