In cases where there are unanticipated demands for services of the office of administrative hearings or where there are insufficient funds on hand or available for payment through the administrative hearings revolving fund or in other cases of necessity, the chief administrative law judge may request payment for services directly from agencies for whom the services are performed to the extent that revenues or other funds are available. Upon approval by the director of financial management, the agency shall make the requested payment. The payment may be made on either an advance or reimbursable basis as approved by the director of financial management.