If you are in an unsupported region, Oculus won't provide support. You would have to rely on whatever warranty Amazon gave you. The same applies to headsets like the Valve index (it has a few more regions than Oculus, but is still limited).
Camera companies are even more extreme, if you are in a country supported by Canon but you bought your Canon camera from a different region, they won't support it (they check the serial numbers).
Amazon has a habit of doing this, selling things in regions where they aren't supported. They sold the Quest 2 to China, even though China blocks all Facebook connections so the Quest 2 couldn't work.
Valve won't sell or ship to Australia. If I got an Index or a Steam Deck imported here, if anything went wrong I'm screwed. So I won't buy them.
You can read the Oculus warranty here: https://scontent-syd2-1.xx.fbcdn.net/v/t39.2365-6/49630950_615501395581577_8065528336517955584_n.pdf...
It says "This Warranty applies only to those countries to which Facebook Technologies ships and supports."
Those are Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Iceland, Ireland, Italy, Japan, Netherlands, New Zealand, Norway, Poland, South Korea, Spain, Sweden, Switzerland, United Kingdom and United States.
If Amazon is selling products to regions that are explicitly not covered by the manufacturer warranty, it should be up to Amazon to handle everything.