Boy, what a sordid tale of abuse of the legal system. You certainly have my sympathy.
Do you think these rednecks would be pursuing anti-trust action unless some lawyer told them to do so? I don't. I don't think they could even tell you what anti-trust involves.
If it were me, I'd look to ferreting out an attorney-malpractice lawyer to determine whether a suit could be filed against their attorneys for defamation or professional slander. Sounds to me as though the basic facts of the case should have disclosed to the plaintiff's attorneys that they had little chance of success. The action was filed in hopes of a quick settlement through allegations of interstate wire fraud and RICO. Scare the bank into coughing up some quick change in a settlement, maybe get a little bonus from that rich appraiser. The plaintiffs themselves are looking for someone else to blame for the fact that they aren't even smart enough to shovel chicken s--t competently, and will never be successful at anything but welfare fraud.
I've found that the legal profession is much like the appraisal profession. We've got our number-hitters, they've got their ambulance chasers. They hate their bottom-feeders as much as we hate ours. If this suit is held to have been specious or meritricious, you may be able to take professional action against the plaintiff's attorneys. At the very least, file a complaint against them with your state's Board of Professional Responsibility (BPR). Ask your attorney if anything these attorneys has done seems to be in violation of your state's Code of Professional Responsibility. (This isn't usually a statute; it is the lawyer's USPAP, and the effect of violation is usually similar.) Get copies of the Ethical Canons (the lawyer's version of Standards Rules) which may have been violated (or look them up on the web yourself) and file a BPR complaint. May not go anywhere, but it'll keep those attorneys busy for a while, and make'em look to their own safety.
You may think that it won't do any good, so why bother? But you never know when your complaint may be just what they were looking for to put some problem lawyers out of business. At the very least, you may make'em take an ethics class and pay a fine--and, I might add, run up their malpractice insurance premium. At the high end, if the Board decides that filing the case invoved even a moderate degree of mendacity or incompetence, then the Board sends their findings to the state's Supreme Court to determine whether the lawyers in question should be suspended or disbarred. Beyond filing and documenting the complaint to the BPR, no other action on your part should be required. If it gets to disbarment level, there's a slight possiblity that you might be subpoenaed as a witness before the Supreme Court or the BPR. Be sure to support that complaint with an affidavit.
'Nother note: Lawyers in most states get informed of BPR actions, just as appraisers are notified of Commission actions against other appraisers. By filing a BPR complaint, your name gets exposed to the lawyers as someone who can get them into trouble. In the future, a plaintiff will have to have a <very> solid case against you to be able to get a lawyer to put your name on a complaint.
This suit is entirely the lawyers' fault, and is motivated solely by greed. Go after them. You'll enjoy the results.