Anyone have advise on a direction to turn to restore my rights?
Obligatory, IANAL. That said I’ve spent a LOT of time on this so I can offer up what I, as a non-lawyer, would personally try. If IL knew about the offense it probably means it’s still in your FBI file. First, although the court doesn’t have the records of the offense, they may still have a copy of the Order to Expunge. My OtE has a statement at the bottom indicating the original is on-file at the Clerk. I would call yours back and ask if they have a copy of the Order. If they do, submit that with a Record Challenge Appeal. If they don’t have it or can’t look it up for you due to lack of records and case numbers I would move on to the next thing.
The next thing I would try would be to request a record search from the Circuit Clerk of the county in which the offense occurred. If it is indeed expunged, they should be able to give you certified proof of non-existence of any records. Try submitting that as your proof to the ISP under the same type of appeal.
If ISP doesn’t accept that proof of non-existence, you may have to do a CHRI through the FBI to get a copy of your record. If the arrest shows up on there and you have proof it’s wrong, they allow you to challenge the incorrect item on your record. Do your appeal online and submit your proof. The FBI can’t directly remove something from the database but they can call courts and law enforcement offices to try to straighten things out on your behalf. Whichever agency reported the offense to the FBI (likely the state police) have to update the record for the FBI to update it.
If none of this works it might be time to get a lawyer involved and a lawsuit started.