How did the builders of ember make sure that the instructions would not be seen for two hundred and twenty years.?

The builders of Ember designed the city with a strict focus on secrecy, placing the instructions for the city's survival in a hidden chamber within the city's underground. They ensured that access to this chamber was limited and that the knowledge would be lost over time by using cryptic language and difficult-to-decipher writing. Additionally, they deliberately set the city's timeline to be self-sustaining for two hundred years, allowing for the possibility that future inhabitants might forget the original purpose and details of the instructions.