Daughter works for an insurance company , she was saying they've had a lot of claims from the Luton Airport fire and some claims have already been paid out !
Won't the insurer of the car that caught fire originally have to pay out for the lot?
Yes, but...
Every car owner will claim on their own insurance as a no-fault claim (also probably will the building owner, and anyone with applicable travel insurance who had their journeys disrupted). Then all those insurers will seek to recover costs from the insurer of the car that was determined as the cause of the fire. If it goes to court (which can take years), the court then buckets up all of the claims by type and makes a determination as to whether each type of claim is payable by the insurer.
All the while, the insurer of the original car will be looking for reasons not to pay out and shift blame onto the driver. If this happens then the driver would likely have to declare bankruptcy (unless he or she is good for £30m or so) and then the insurers may be able to claim out of a pot that they all have to pay into for uninsured losses. If they can't then the individual insurers will have to take the hit on behalf of their clients.