Diamond Princess - Visa questions

Hello everyone! We are a family of four taking our first Princess cruise aboard the Diamond Princess booked for this February 17th, leaving from Brisbane and travelling up to Yokohama, Japan.

We are trying to make sure we have sorted out our visa requirements for ports of call

Although we are leaving from Brisbane, we are Canadian citizens. The princess website includes visa requirements for Australian citizens but not for Canadians, and Papua New Guinea is not as straightforward as I thought it would be.

According to what I have read, Papua New Guinea requires a $50 electronic visa for tourists, and stipulates that visas are not available on arrival, but there is conflicting information about whether or not the cost is waived for cruise passengers. For example the princess site says that Australian citizens will be issued a visa on arrival and there is no fee associated with it.

As Canadian citizens, can we use the same no-fee electronic visa-on-arrival as the Australians? Or should we purchase our electronic visas in advance? We tried calling Princess and they would not give a clear answer other than to say it is our responsibility to make sure we have the correct travel documentation.

Anyone have experience at this port of call and able to weigh in?