No sum payable under this act to a veteran, or to any other person under this act, shall be subject to attachment, levy, or seizure under any legal or equitable process, and shall be exempt from all state taxation. No right to compensation under the provisions of this act shall be assignable, except as hereinafter provided, or serve as a security for any loan. Any assignment or loan made in violation of the provisions of this section shall be held void: Provided, however, That assignments to any group or organization of veterans, incorporated or unincorporated, or to any nonprofit corporation heretofore formed solely for aiding disabled or incapacitated veterans, and assignments to the State Veterans' Commission, shall be valid. The State Veterans' Commission is hereby authorized to accept such assignments, which shall be treated as confidential, and the funds realized from such assignments shall be expended by said commission solely for the aid of needy veterans and their families. Except as in this section provided, the Adjutant General shall not direct the payment, nor shall payment be made, under this act, to any person other than a veteran, or the representatives of a veteran, as in this act provided.