The alleged crime happened in a foreign and independent country, where they have no choice but to play by the rules of that country. That's why. Non-cooperation just makes it worse, ensuring that nothing at all gets done.
How about tapping into the local universities around you ? Plenty of universities nowadays teach intro-level courses in machine learning. Someone who has gone through such courses would know more than enough to satisfy your needs. I'd love to help, but I'm not based in Amsterdam :)
Failing that, there're always online resources to turn into. I highly recommend this https://class.coursera.org/ml/lecture/preview. This is how I got started with machine learning too. It's not hard to hack together a basic recommendation system quickly ... although for the long term, you might need a dedicated person to work on it since providing good recommendations on favourites seems to be your core value proposition.