The fees involves are the single biggest factor that make it difficult for victims to take scammers to court. It might be possible for you to find a suitable lawyer by contacting others in the forum that have taken casinos to court (including Curacao).
As for the police, if there is a way to get them involved it would certainly be a serious escalation on your part and just might force the scammers to pay what they owe you.
I'm still looking for a lawyer who will not charge me an unreasonable fee upfront in return for no assurances (like $2000 for typing out a short letter). I suspect that many lawyers immediately think anyone with any bitcoin has unlimited amounts of wealth at their disposal.
Of course I would be happy with paying the lawyer up to 100% of the amount in question (which is nearly $7k). So if you have any leads, please do share them!
I'm also continuing (in a few ways) to push police to go after them.
The police are already involved, they are just not very willing to help.