19.445—What action may I take if a primary tier participant knowingly does business with an excluded or disqualified person?
         If a participant knowingly does business with
 an excluded or disqualified person, you as an
 agency official may refer the matter for
 suspension and debarment consideration. You may
 also disallow costs, annul or terminate the
 transaction, issue a stop work order, or take any
 other appropriate remedy.