Releasing a rabid dog into your own backyard? I don't think you realise how much that would affect any political individual/party. This isn't even at a national scale either, internationally you would get utterly panned.
If you genuinely believe such a thing could happen there you also have to accept the equally absurd notion that some peanut in power will do absolutely the same thing here. It's also not hard to see someone with an axe to grind in NZ thinking 'nah we don't want him, your problem' and dumping over the ditch as a threat.