I taped the race, and IIRC it wasn't just DC he overtook. He came out next to DC and passed the cars until he got to behind Kimi, so I think he passed more cars, not just DC., and even so, he had to let all of the pack go by and rejoin at the back. And even if he didn't look for the light, it's virtually impossible not to see it.
It's McLarens fault for keeping him out too long anf his for not stopping at the light.