I am a long time Realtor in Marin.
I am not sure how to direct you maybe another person will know. What you are asking of a Realtor is how to bypass what we do for a living and how we make our living, by selling real estate.
Our job is to get the listing, market it and close the deal. Sometimes this takes months of working with the bank. It is never easy to deal direct with the bank and my understanding is they don't like doing it either. With that said you are trying to buy the house before anyone else knows about it and I applaud you for your insite.
I wish you good luck.
You should be able to go to the county and do a title search. I am sure you can do this online as well through the county.