[Elaine "Lady Blue"]

Remember what ASA school clinicians have always taught us:
"If you deviate, communicate" The veteran PU should have been communicating to the rookie "you've got the runner to 3rd!" or barring that when PU went to 3rd, "you need to cover the play at home!" Something, not just silence. Rookies are nervous and sometimes petrified on what to do, so you must direct them.