Thank you so much for your reply. I will follow up on that obituary; that might state a burial place!
I really appreciate you taking the time to do some research in the death indexes for me. The Catherine (Haviland) Rushmore that you found who died in 1897 is my relative as well; I did see her grave at the Ogdensburg Cemetery. There's another Catherine (Vosburg) Rushmore (wife of Durenty), and she and her husband are the "missing" ones.
Thanks again! :)
Sincerely,
Mary Packard