PDI's are done by all dealers of any type of vehicle, from a bike to an rv. You can be present for it, if you wish, but thats not normal, or request the check list by the technichin that did the inspection. There could be several as each may have a field of expertise. Rvs are very complex.
In your walk through if you have questions about a particular system, ask to speak to the tech. that initialed that pdi check list for in depth description and knowledge of that system if the person giving the walk through does not answer your questions to your satisfaction.