As someone who has coached high school-aged kids -- boys and girls, in a variety of public and private school settings -- I can tell you that communication is NEVER a problem for those adults who do so with respect. In theory, the kids selected as captains are chosen for a reason: their leadership skills, ability to communicate with officials, responsibility, etc. For an adult to simply ASSUME they can't or won't listen clarifies the issue entirely. Why even have referees if you assume the kids just won't listen?
What a lousy attitude for a responsible adult to take.