The first "error" is in fact not error at all.
In David's POV, she is constantly referred as "High Epic".
Only Tia reclaimed that Regalia is not High Epic.
Even the book description reads:
"Babylon Restored, the city formerly known as the borough of Manhattan, has possibilities, though. Ruled by the mysterious High Epic Regalia, Babylon Restored is flooded and miserable, but David is sure it's the path that will lead him to what he needs to find. Entering a city oppressed by a High Epic despot is risky, but David's willing to take the gamble."