I encountered an incident some years back when a departing EK 380 FO suspected icing on the wing based on the view from the taxi camera. He insisted on personally viewing the wing even when told it was just condensation and explaining the facts and that the elevated platform would take 30 to 45 minutes to arrive. Location : Singapore. Aircraft was departing after a scheduled 6 hour ground time. Aircraft departed with a delay of 1.5 hour.