The priest isn't much help, besides being fixated on silence. See what else there is here that you can use.
Hint 2
There's an odd book in the middle of the room on a kind of lectern. Check it out.
Hint 3
It's essentially a collection of anonymous prayers. How very odd. If George Ostin wrote a prayer here, it might help us -- if we knew what his handwriting looked like.
Hint 4
Oh, wait, we do. Remember the note about the clothing drive? (If you don't have it, go back to George's building and have Joey blow the note over to Rosa.)
Hint 5
Use that note on the book to find George's prayer, which gives you another name to go on.