Is this really legal?

If a parenting plan and divorce decree have been signed by a judge, even though the petitioner has declared in both doents (I'm uming she did it simply out of ignorance) that the court has no jurisdiction, wouldn't that make the orders null and void? And another question. Can the petitioner list a certain attorney as the court ordered mediator (instead of the standard county mediation provider) and then after the divorce is final, hire that attorney to keep trying to screw with the respondent? Wouldn't that be a conflict of interest for that lawyer/mediator to represent either one of them? And 1 last question. A year and a half after this "divorce" was finalized the petitioner asked the respondent to sign a quit claim deed for the property awarded to her, and he agreed as long as she would sign one for the property awarded to him. She called and told him she had the papers signed at her lawyers office and just needed his signature. He took time off work to get there just to find out that the only paperwork was for the land she wanted, nothing pertaining to his. He refused to sign and now she's threatening to take him to court and get lawyers fees from him? How can she do that when he made a good faith effort to sign the papers and she lied to him and tried to trick him into signing them even though she had no intention of signing the others?