'Being over the edge of the world' itself had little to do with the disaster.
Step-by-step explanation:
In "the Hobbit' the allegory of being over the edge of the world is about the adventure being completely off the charts and never having been something like that before, which was of course untrue.
But for the characters concerned, it indeed was true.
Characters with Beowolf like characteristics would be well prepared for a disaster because in a way they signed up for it.
Smaug and other figures of 'disaster' are prophecised as a part of the journey.