The Worm That Devours (Demented starting quest) can be simultaneously won and lost

[Bananadine]

If you leave Kroshkkur, the countdown to the worm's arrival starts. If you return to Kroshkkur and then hang around inside it for a long time without entering the worm, then the worm will arrive and destroy Kroshkkur.

Expected behavior: Either one of the following would be fine.
1) You instantly die. If the Eidolon revives you, you are not sent back to Kroshkkur. If you somehow have extra lives from another source (very unlikely I think?), you simply lose them all. If you have a death prevention ability like Cauterize or Second Life, it fails.
2) You get a text blurb saying you've escaped somehow; you're automatically booted out of Kroshkkur. Since failing the quest already stops you from ever returning there, that's good enough.

Actual behavior: The quest is failed, but Kroshkkur remains unharmed, though you do lose the spell for teleporting there. You may enter the worm and complete the quest, at which point your failure becomes victory. Without your teleportation spell, you can only leave the worm by using the Rod of Recall. You can never return to Kroshkkur, even though your quest log claims you prevented the worm from destroying the place. Weird.