There are four of them trying to keep the thing balanced, but that doesn't matter. All that matters is that Ben's there, and it scares him so much, telling them that he'll stay, but he'll do it, for Ben. Ben, who gives him a look full of gratitude, then turns back to Abby. He knows it's wrong, but he wishes it was Abigail staying, wishes it was himself that Ben looked at with so much love in his eyes. But Abigail disappears up the ladder, and the two of them are left.
Then the thing – he's not even sure what it is, Ben probably knows – begins to crumble, and Ben urges him forward. He hesitates only for a second, and then runs. Hanging off the ladder there's only one person he can think of, and it's not himself, he turns, sees Ben run then jump and somehow he catches him. Standing on the rock ledge watching Ben and Abby embrace he can't help but think that if he and Ben hadn't of made it; at least they would have died together.