Involved in a pile-up in a slow traffic. A luxury car bang 3 cars before hitting mine (direct impact), and my car lunge forward and hit a 4x4 in front.

Let say, if the driver of the luxury car lost conscious before hitting all of us, is there any complication in claiming? And who should/can I claim it from, beside OD?

Any assist in this matter will be appreciated.

Thanks for the input. Just received call from traffic department yesterday evening, the sergeant said it's a no-fault collision thus all 5 cars can only claim own insurance (NCD unaffected).