What ICA actually asks for
A PNG address matters, but accommodation uploads are not universal across every visa class
ICA's current Visitor Visa page says applicants must show that they are genuine visitors who intend to leave Papua New Guinea at the end of their stay. It also says ICA may request supporting evidence depending on the traveller's circumstances.
ICA's Entry Permit application form includes a dedicated PNG residential-address section asking for the number and street, town or village, province, postal address and local contact numbers. That makes a clear, usable PNG address an important part of application preparation even when a specific hotel voucher is not listed as a universal upload.