You may call it trust. I call it fear.
Fear of the Triumvirate/Quintenal Cabal and the Supreme Septat.
That’s what basically keeps the peace. However, officially, what you say is what those 13 also say. Some demons believe them, and the rest just obey or die or worse…
People who don’t particularly agree with the 13 Lords of Dread generally stay away from the Courts in their own palaces or their own smaller cities (where they are the rule of the realm)
And as for Angels, there are angel like figures in several Native American mythologies, but they are more seen as ‘spirits’ than angels…and some also have gods…
The Kabalah actually details in great great detail the nature of the Judeo-Christian-Islamic heavenly and infernal structure, over the millenia there have been an inordinate number of religious scholars describing, debating and listing these angels, demons and their relationships.
Also a lot of the traditions of djinns and early angel/demon stuff came from really old now defunct religions that most of us have never heard of…i.e. the Ancient Hebrews used to borrow supernatural beings almost as fast the Catholic church. They just turned foreign gods in to demons or angels, whereas the Catholic church mainly turned them into Saints…but sometimes Angels and demons.