Wordplay derived from "The elephant in the room" phrase: important issues or subject matter that people tend not to want to discuss, thus overlooking the isuue.
Redlight is a reference to a traffic light; homeless often stand at traffic lights to aquire money from passing drivers.
Jen and Mike were approached by three homeless coming out of the bookstore. They didn't hesitate to walk past without making eye contact. Neither addressed the Redlight Elephant on their walk to the car.