Key to success is finding a good attorney. The chap must be 'pre-eminent' in this kind of litigation. He'll be terribly expensive, but the initial meeting will probably be free, a discussion of the case and its merits. I'm not sure how to follow my advice but attorneys have access to their peers' qualifications and will share if he happens to be friends with one. Otherwise google for similar cases, which often name the attorneys, and then check them out.
Fun as the lien sounds, it's unlikely that Cathay will neglect to pay up if they lose.