Where by reason of the absence of records or other circumstances making it impossible or unreasonable for the director to ascertain the names and addresses of all the depositor creditors, the director after exerting due diligence and making reasonable inquiry to secure that information from all reasonable and available sources, may make demand on a warehouse operator's or grain dealer's bond on the basis of information then in his or her possession, and thereafter shall not be liable or responsible for claims or the handling of claims that may subsequently appear or be discovered.