> doing so would be a violation of their vows of silence

I don’t know what this means. There is no formal “vow of silence”. The closest things I can think of are the discipline of avoiding unnecessary speech in some monastic communities, or perhaps the seal of confession, but this doesn’t apply as priests can speak in generalities or anonymously about the kinds of moral issues people struggle with.

> Good homilies are written with the particular community in mind.

That’s a bit of a generalization. Many, if not most, readings simply benefit from clear explanation. Tying in local or cultural context can be helpful, but they can also be a distraction, and mostly, homilies should be about the essential meaning of the readings. By having to write the homily, the celebrant benefits from writing the homily as well, a benefit he would lose if he simply drew from a corpus of prewritten homilies.

Catholic priests are forbidden from revealing anything they learn in confession under ANY circumstances. If someone comes in and confesses to a crime or that they are planning a crime, the priest can advise them to go to the police, they can counsel them that they may be in danger of hellfire if they do not, but they absolutely cannot tell anyone. The Catholic Church takes this very seriously. It is fully expected that a priest would die rather than break the confidentiality of confessions.