I already had another case 3 years ago and the result is that the attorney is part of a big lawyer office with hundreds of lawyers who are working international to collect fees from people doesnt matter where they live.
In my last case Im protected because I have a proof that I was abroad and informed the guest before. I just mentioned the case here to find a better solution for the guest. But it seems there is no better solution at the moment.
I can recommend to all hosts in germany: If you are not responsible for the illegal download/filesharing dont pay anything to this attorney office. You are not responsible for the crime and they will go further to find your guest when you provide the name and the booking details.
As HOST you can protect yourself:
1) when you collect the resident addresses from your guests (its not necessary but it helps a lot)
2) when you write in your listing that you are not responsible for any illegal internet behaviour
3) when you have a proof that you were not in the apartment during the crime was happen
You dont need to hire a lawyer!
4) you can offer every guest his own internet access with an additional device (for example Sorglosbox or Beschützerbox)
5) if the crime was happen answer fast the lawyer and send your proofs to avoid higher fees for the guest
As GUEST you can protect yourself:
1) have a proof what kind of device you use during your stay at a hosts place (in case that your host did the illegal download and is blaming you because you were both at the same time in the apartment - only the used device is than a proof who did the crime)
2) use always your own device, dont use a device which is offered from a host when he/she is using the same device (reason above)
3) use VPN (speed is mostly not fast enough for a download)
If you already did the illegal download/filesharing you can avoid high fees:
1) when you pay immediatly the fee (mostly 30-50% less than scheduled) for this option it helps to hire a lawyer to get more discount
2) when you find a solution between both (host and guest) to share the fee (only possible when the host has no internet rules written in his offer)
If you never pay because you living abroad and you think german or EU laws is not valid in your country, you will get a title on your name in germany. This means you will get problems when you visit the country again (also years later!)