Grullo's cart arrived playing 'Mack the Knife' with its follower right behind it, and its people got out.
Grullo delivered. The abyss cart came through still blasting its trap song — "Mack the Knife" for the Grullo line — and the trainyard cart followed minutes later, close enough to prove Carl's theory that a cart slows when its Debris Scoop hits something big, and far enough back not to be eaten by the portal in front of it.
As on the Sinopia Line, the abyss gate at the end of Grullo did not line up with the associated trainyard track, so the crawlers who went through never saw the cart again; they walked out into the yard and made their way to the closest instance of Station 36. Eight hundred people between the two lines, all of them now behind a garrison at a stairwell station — the best, Carl says flatly, that he could do for them.
That left Mindaro Line as the only line whose people were still stranded, which is why the party climbed onto a cart and drove seven hours to find out what had gone wrong.
Never travelled by the party. Present only as a song heard arriving at the far end of the world and a count of people who lived.
The second successful rescue line — both carts arrived, and its stranded crawlers reached a stairwell station.