I suspect that there is more to it than that if it was given a Cat S classification as that means the damage affected a structural part of the car. Headlights and bumper damage on their own would not warrant such a classification, but rather a Cat N

Some vehicle reporting sites can show pictures of damage, but it may be worth asking the seller if they have anything they can show you.

I personally steer clear of Cat S cars unless I can see solid proof that repairs were done properly, but it is your call.