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Based on your description, I am not clear if you have proof anyone been "feeding" information to your new landlord, or this is your speculation. To the extent you were a party to a lawsuit --whether as a plaintiff or defendant -- anyone can find your name in a court index search. Be sure to consult your own attorney to protect your legal rights.
Unless court records are sealed, anyone can do some digging into old cases and obtain information. Maybe you should have a heart-to-heart talk with new landlord and keep him or her happy.
The answer is maybe. You write that "I made sure that the owner couldn't blacklist me to tenant screening sites, credit bureau(s) or any future landlord." Assuming you had such a stipulation, then the landlord's attorney might also be bound by it on an agency theory. The landlord's attorney, as the agent of your former landlord, might be liable for you, therefore, for tortious interference with contract, or some other tort. It is hard to opine further without knowing more about the agreement.
Important things to remember: 1. The fact that I answered a question that you asked me on line, doesn't make me your lawyer. 2. Opinions are like noses--everyone has one. I just happen to think my opinions are right, but check with another lawyer too.