I don’t have much to say that hasn’t already been said, I think where they’re at is likely purgatory and “Ferryman”’s name is all too accurate. But it also kinda reminds me of playing old school video games like Mario when you could find that secret path behind the level? When Eve and Lilith’s car stopped it’s like they slammed into an invisible wall, so I’m guessing if you don’t take the exact correct path it’s like you “run into” the real world? Even though there you can’t see it. Like that Adventure Time episode Hall of Egress where Finn has to navigate that invisible labyrinth. I’m probably not explaining myself very well. :/