OIG Authority
The IG Act provides the OIG with unfiltered access to any and all information available to the Board that is needed to fulfill the OIG's responsibilities under the Act. Furthermore, Board policy states that all officers and employees of the Board are expected to cooperate with and be responsive to information requests and questions asked by OIG auditors and investigators in connection with an OIG inquiry.
http://www4.law.cornell.edu/uscode/html/uscode05a/usc_sup_05_5_10_sq2.html

Duty to Cooperate with the OIG
All Officers and employees of the Board have a duty to promptly report instances of fraud, waste, abuse, misconduct, or criminal activity in Board programs and operations to the OIG. Employees concerned about possible wrongdoing can contact the OIG in person, in writing, or by telephone call made to OIG staff or the OIG hotline.

Employee Protections
Individual’s who report fraud, waste, and abuse through the OIG Hotline may remain anonymous. In addition, the IG Act provides that the OIG will not disclose the identity of the individuals who come forward with information without the consent of that individual, unless the IG determines that such disclosure is unavoidable during the course of an investigation. Furthermore, the IG Act protects employees from reprisals or retaliation for having reported a complaint or disclosing information to the OIG.