Clearly something didn't work then because if the red lights were on, no one queried ATC instructions to cross despite the red light. Or weren't they on? I guess the NTSB will reveal that at some point.
Shades of the TCAS-related collision in Europe where the Russian aircraft followed ATC directions and the other aircraft obeyed TCAS. There needs to be a clear direction here that if ATC conflicts with other signs then a query should be made. It's also a use for the green light at the end - explicit clearance confirmation for the departing aircraft.