After explaining how they got there, Nightingale asks Abigail for a way to temporarily lift the Aegis stone and enter the Eerie, so that they can free Justice and retrieve her part of the Pontifex.
Tyrial insists this is impossible, explaining that the dragon-slaying mural on their wall depicts the way Lo and Ida obtained it in the first place. They had to travel the Middle Passage, make a pact with a demon, then enter Arkalla and kill a dragon within. It would be impossible to recreate their feat.
There is no way to open the way into the Eerie. They ask Zeke if Justice would want to sacrifice the lives of everyone in the city to save herself. He admits that she wouldn’t.
Abigail tries to reassure Nightingale that they’ll feel better tomorrow, and might be able to figure out what to do then.