Hello, and welcome. I am a licensed attorney and happy to assist.
I'm sorry to hear of your situation, but happy to say that you do have recourse if appropriate steps are taken. It sounds like the person ultimately responsible for this chaos is the attorney who gave you the wrong information and negligently misrepresented the agreement. That said, you've been summoned to court and the judge will not simply absolve you if you point to the attorney. You will need to properly respond to the summons and complaint and also file a counterclaim against the attorney for indemnification and damages.
It is important to respond to the summons within the allocated period of f time so you do not end up with a default judgment, so that's the first thing to be done. A counterclaim against the attorney must be filed at the same time as your answer, or you may lose the right to have the appropriate person held responsible. You (or better yet, an attorney acting on your behalf) can also contact the attorney and let him/her know your anticipated course of action, requesting that he present this matter to his malpractice carrier.
This is clearly a complex matter with a lot of parties and facts involved, so it is best to have a local attorney handle all of the filings and representation on your behalf. A good referral source will be your County Bar Association. There should be no charge for the referral and no cost for the initial consultation with the attorney to whom you are referred. If that attorney takes your case, there may be no out-of-pocket or expenses to pay, either. That attorney will be able to review all of the details pertaining to this matter and act accordingly to best protect you and give you the peace of mind to go forward without worry.
I hope this helps. If you need additional information or clarification, just let me know and I'll continue to provide assistance. If I have addressed your issue and/or pointed you in a positive direction, please let me know that, as well. Also, please remember to leave a positive rating when prompted, as that is the only way attorneys on this site are credited for the help we provide.