In general: You have to find a weak spot. I have problems with a scam (ongoing) in an East European EU country and I have been trying to get the authorities for 6 months to act. Even hiring a lawyer has been extraordinary difficult. Most don't reply Emails, others charge exorbitant fees, our last lawyer is MIA so we are trying now with a lawyer that is listed on an embassy website. We are talking here about a loss of a mid 5 figure sum.
After nothing worked, I listened to the advice of a local friend and started to expose people from the government/police that do not act online. Very bold, very nasty, very below the waistline. But now it looks like I finally bombed them to the negotiation table. :-)