Until some future story, if it ever exists, canonises that it was somehow destroyed, my preferred line of thought remains that it simply went on tumbling forever.
This fits much better with the general themes. In mythology, typically something dangerous or even demonic is unleashed by unsuspecting adventurers and, while they don't have the means by which to literally destroy it, they can expel/banish it. It isn't dead, but it is rendered harmless, unable to cause further harm. It becomes a warning to others not to venture too close or risk similar consequences.
This feels like a modern update on that idea. 'Hellraiser' did this, too: Cenobites got exiled back where they came from.
