You are right, in her case, it is better to just buy Princess Platinum protection (they are both Platinum so will only need to pay 6% of cruise cost).
Her final payment is mid-January, and cruise is mid-April. Due to staff shortage, niece's boss said he will not be able to approve vacation until 2-3 weeks before cruise start.
Next week I will call my CVP to pay full payment for my next cruise, at that time, I will ask him how this cancelation works if one doesn't want to buy the Princess Platinum Protection. Majority of the time, I do not like to buy PVP, because most of my cruises are long cruises with many sea days. PVP's Emergency Medical Evacuation coverage amount is too small.