old judgement

I have an old judgement (2006) on my county public records. My wife at the time was not turning our rent checks I gave her. The apartments filed a judgement. I found out when I received a court summons one night. I appeared in court. The judge said we could work out an agreement to pay and the judgement would be dropped. I stepped in the hallway with apartment manager and discussed what had happened. She said I could pay that day and the judgement would be dropped. I paid in full that afternoon. I thought everything was taken care of. I have been pre-qualified for mortgage loans, and received car loans and personal loans since then. Now I am being denied a mortgage loan from the same lender because there is an open judgement on my record. I talked to the corporate office that owned the apartments. They sold the apartments shortly after this judgement issue. They don't have any records of this and said they can't help me. What do I need to do to prove payment and have this judgement cleared and removed?