[... So awkward. He'll pretend you mean logistically.]

We know how to open a portal to a nexus world. It doesn't work here, but we're hoping that's because of the power dampeners inside the barrier. So ... if the Key works, and if we can open the portal outside the barrier, then we can get home. You can probably find a way to your world from there too.

[Sigh.] It's a lot of if's. But it's the best we can do.