If the belt broke, and the engine was shut down, there is a good chance that there was no damage, you will have to search, unless someone answers, to find out, I cant recall if the vg33 is an interference engine or not. search some sites, I am sure you can find lots and lots of info about that subject, I know I've read a few things related to that topic.
As far as putting a 99 pathy into it, not sure that would be very cheap or easy, would probably cause conflicts if not changing the computer out too...