"What power do foreign government agents have in these situations?"

Guns and strong arms, I can only assume..

"Could someone explain how Austria permitted slaves to be held within its borders?"

I agree with Dominik that that is a rather offensive question. Ofcourse it doesn't, even Kim himself did not believe she was a slave still, of course she was and felt that way.

There's only one way to assert that you are not a slave, and that is to test your freedom.

I don't know about these cases specifically, but usually it is done by threatening their families back in the other country.

Hmm? The eight years in captivity was in North Korea. She convinced her minders to allow her to visit Austria, and made her escape after soon as she could once she landed.

Elsewhere in the story the translator had a Dominican passport. It seems likely they traveled using forged documents and first, to Japan. Kind of like how Americans go to Mexico in order to get to Cuba and vice versa.

Did the Austrians realize she was a slave? Did she realize it herself, for that matter? Everyone has stereotypes when it comes to slavery, and it's actually pretty hard to detect it, especially when the victim has been institutionalized as I can imagine this woman was.

I second that, this is very curious.

Well I'd imagine they left it off the customs declaration

You must be seriously brain damaged to ask such a question. I am from Austria and I can assure you that there are no diplomatic privileges to hold slaves in my country.

I also live in Austria.

Of course there is no official way to hold slaves in Austria. However stories of foreign diplomats that hold "household staff" under slave like condition surface with saddening regularity.

Very often they are stripped of their passports in a country where they don't speak the language, so their perceived options are very limited.

Being a UN seat with a lot of diplomats certainly aggravates this problem, as do the restrictive immigration laws, that do little to protect people that want to escape from such circumstances.

Also in the case of the actress, her perceived options might have been very limited, while in practice the "only" thing she would have to fear after defecting would be assassins sent after her. Scary enough.

So I also think the question shows a limited view of the world, but is not offensive enough to accuse someone of being brain damaged.