At the very least, a successful criminal prosecution would make you feel better. And it would likely advance your cause...I'm not sure if an extortion conviction would be admissible in a civil trial for something like this, but even if it weren't, the fact that someone was convicted of criminal extortion would make it far more likely you'd get a good attorney to work on contingency for the civil complaint. Even if you only recover $1m, 33% of that is a decent payday for a lot of lawyers.

Well, it might. If you don't have the resources, could you in fact pursue the extortion charge, get the judgement, and then come back around and say "hey, now that you've been found guilty, let's talk about the real issue"?

They may be willing to negotiate at that point. Of course, not a lawyer here.

Can you not follow civil and criminal routes? Find an attorney to take the civil cases (and file for patent infringement, the ownership issue & the extortion), and at the same time report them for extortion.

Assuming everything is well timed you could have 4 guns blazing at once, which will certainly help them notice you. :)