You need an attorney. My state does not allow one to dissolve and adoption unless their is another familiy willing to adopt the child. Not sure if Illinois is easier to deal with or not.
Often adoption subsidy will pay for a child to go to a group home or residential setting if they are unable to live at home. Again, varies by state.
You might want to go to
Welcome to Attachment & Trauma Network* - ATN and request to be on their support list. Someone there may be able to give you information. I know their on many Illinois families on the list.