I'm not sure where you're based, Mr. Connick; but the Louise Hanson-Dyer Music Library at the University of Melbourne has something litany-related on its shelves by Muset (who, I believe, spent some years in Australia). Here's the catalog entry for the music. Would it be worth following up this via Interlibrary Loan? (You'll notice that nothing about Volumes 2-4 is mentioned here.)
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