Bizarre, tax/tariff evasion or "Mistake" does seem like the most likely explanation - yet US$1.4m is too little to bother evading tax on really. I mean that could be a refit on a boat or something -- $1.4Mn is literally nothing.
Pity the Faulkland Islands, population 3,200 and about a million penguins. They have a 42% tariff.
Are you feeling great again, Americans?
Now it is 1.4 mln, in future this could be 1000 more, if this will help with overcoming tariffs. Check what happened with Germany export to Kazakhstan in 2022.
The Guardian has investigated further: https://www.theguardian.com/australia-news/2025/apr/04/revea...
In the case of Norfolk Island, it was apparently some mislabeled shipments from Timberland (based in New Hampshire, NH <-> NI) and from two companies based in Norfolk, UK.
For Heard & McDonald Islands, it was mislabeled machinery that actually originated in Austria and Germany.