Some places by policy you are required to hang paper on someone, that is a fact. With that in mind the prosecutor and then the judge can choose to not file or dismiss the ticket.
Sounds like the trooper was having a day that required everyone to get a ticket. Driver of the car, both good samaritans, and possibly later both elderly females.
IMO I would pick what factor contributed the most in causing this accident. Speed to fast for conditions, or failure to maintain control would be for the driver in this case. The insurance companies can argue in civil court and they will no matter who gets a ticket.