I know you’ve focused on higher end international guests, but could you pivot from inbound to a focus on domestic tourism for the next year. The key will be to add experiences to the courses in the itinerary but also take the hassle out of it all. There are many NZ golfers who will remain able to afford Kauri, Kidnappers, Te Arai etc with extras. One option would be to secure special access from the top courses now before they reopen.
I also agree with Anna to broaden beyond golf and offer hand-curated hard to organise experiences. After being locked up for some time many kiwis will want to have an experience of a lifetime. You could help them plan it now whilst they have time in isolation, secure good rates from top end places, and secure deposits from customers.
At some point the borders will open again but it’s likely to be slow and selected countries, not all, and not necessarily your main markets like AU and USA. However as each one does you can add it, and offer tours to NZ as well as tours to that country.
Lastly, keep up your international marketing, just extend your timeframe for conversion and a return to your original vision.
Hope that helps.