You are not likely going to get those recordings or minutes of the closed sessions because of the IL Open Public Meetings Act unless this suit is about enforcing the Open Public Meetings Act.
Bolding added.(e) Unless the public body has made a determination that the verbatim recording no longer requires confidential treatment or otherwise consents to disclosure, the verbatim record of a meeting closed to the public shall not be open for public inspection or subject to discovery in any administrative or judicial proceeding other than one brought to enforce this Act.
Sec. 2.06. Minutes; right to speak.

