You might try the Mariposa county office of Records....All sales are subject to Reconveyance of title and needs to be recorded.
We just encountered the same problem, the home we are purchasing had a clouded title from the estate of previous owner. The same real estate broker handled the deal but did not have any of this info on file. This occurred 2 yrs ago. our daughter in law entered into contract to purchase and not until we had become coborrowers and asked questions did we find out the problem. We did an extension so they could clear the problem. We refused to go forward until they had clear title and had notification with copy of recording.
Good luck. Mariposa County has a lot of clouded ordinance issues that can be a problem if trying to resale property. Check out the ordinance on Septic tank Leach line and Well rules.