@Anton Ivanov, you make a very good point, (which seems to be overlooked by a lot of people judging from your votes up).
Scandinavian gamers/hackers wouldn't use an American server, the ping would easily be up in the hundreds of milliseconds. That may not sound like much latency to non-gamers, but it would be laughed at as unusable and pointless by gamers.
I wonder if this is an insider job so to speak, where it could simply have been setup by an in house IT worker as a gaming server for him and some friends, all likely based in America. Maybe someone tried to connect from Scandinavia but I doubt they would have got far in the game. There may very well have been no actual hacker, but simply some IT worker using the medical server as a gaming server and now its been found, they know they are in trouble and so are trying to cover up what they did by saying, oh it was hackers, I'll help you find them. Problem is the paranoia around the word "hacking" these days could easily result in non-technical managers freaking out at the word "hacker" in association with their beloved servers. Which would just dig a bigger hole for the worried IT worker.
(I've even worked in companies where we have put gaming servers on office servers, its just the bosses were ok with it (in one case, they even joined in :) ).
Also a gaming server is likely to be a lot of data, when adding in all the maps data, so whilst not impossible to upload, its a major pain to upload it all. Much easier to install if you just do it via an internal intranet connection.
I bet its just a now somewhat worried IT worker, trying to say it was hackers. :)