Compulsion shall not be a defence to the taking of any such oath or engagement as aforesaid, unless the accused, within 14 days after taking it, or, if he is prevented by actual force or sickness, within 14 days after the termination of such prevention, declares by information on oath before a justice, or, if he is on actual service in His Majesty's forces by sea or land, either by such information or by information to his commanding officer, the whole of what he knows concerning the matter, including the person or persons by whom and in whose presence, and the place where, and the time when, the oath or engagement was administered or taken.