^^^^ That last scenario is correct.
Given that the car was imported in 2005, it's entirely possible that it had those kms on it when it arrived in Australia, but as far as verifying mileage goes, the documents they've sent you don't make a very convincing case either way.
The fact that the owner has held on to them for 5 years, however, points to someone who keeps their documents in order, which usually also points to a well serviced car. I think it's worth going over to have a look at it. The paperwork's not ideal but it's better than most.