This is all good info. Maintaining a DP isn't that bad but, they are all different and if something is overlooked, it will get expensive down the road. I maintain my own diesels and have done a number of complete overhauls in my earlier days so have no problem dealing with whatever comes up. But, each engine model is different than the next and they all have varying maintenance requirements. When I first got my 400 ISL it took me a while to put together all the details of what to do and when to do it.
To try to do this stuff yourself without a thorough understanding of the service requirements is impossible. There is no way any one can give you enough info on a web forum to turn you into a service tech on that particular chassis/engine combo. The best thing she can do is learn an understanding of what the service schedule is and then have it taken care of by a dealer. Newmar can give her excellent advice about what is needed and when. They can point her in the direction of a suitable service center so that things won't get missed. That, and a repertoire with a local dealership will go along way to ensure that everything goes smoothly.