If the director has a reasonable belief that a registrant, or person or entity acting in a capacity that requires a certificate of registration, has engaged in activities prohibited under this part, he or she may submit a written request to the registrant, person, or entity, requesting copies of written material related to his or her investigation. Any registrant, person, or entity receiving a written request from the director for information related to an investigation of prohibited activities shall submit that information to the director or the office within a reasonable period of time, which shall be specified by the director in his or her written request. Any material submitted shall be kept confidential by the director and the office.