I was involved in a jet ski accident 2 years ago. The jetski I was driving was rented, and the rental company did not offer insurance ( it was not required in nevada). I had a head-on collision with another jetski. I tried to avoid the collision by turning away from the other vessel, but he turned into me. I paid the full cost of the jetski I was on to the rental company, and had never talked to the other party involved, only the police. Now two years later I have been contacted by a recovery service agency stating that I owe them for the $6,000 in damages to the other jet ski. They also stated that if I refuse to pay, my driver's licence will be suspended, they will take me to court, and I will have to pay their attorney fees. None of this really makes sense to me, and can they sue me two years later, and win?

Anyone can sue you, winning is another subject.

If the official police report indicated in any way that you were at fault, then the chance
They will prevail is pretty darn good.

Have you seen a copy of the police report?

Who are they representing, the other renter/driver or the rental company?

I say the key here is what is stated in the official report, that is what you need to take a look at.