What do I need to reopen a discharged bankruptcy case?

Inform the trustee of the potential recovery in the lawsuit. Let the trustee decide whether to reopen the case.

It's too late. I am assuming they are trying to dismiss your case under a doctrine of collateral estoppel. The law says you cannot take one position (that you do not have an asset) then take a different position (I have a valid claim (asset) in another proceeding. I do not think you have the defense that you did not know you owned the asset since you filed bankruptcy 2 years after you filed the lawsuit for wrongful termination. You should talk to your attorney on the wrongful termination case about this issue because frankly I do not think you can save the case now, especially since you are only seeking to add the asset to save the case. You also do not have the defense you did not know you were supposed to list that an asset because the bankruptcy schedules clearly ask you if you have any interest in an lawsuits. I am not sure why you did not list the lawsuit an asset but I think it has cost you this time.

Hire an attorney you will need one.

File a motion to reopen your case.

A Chapter 7 case may be reopened by Motion and by paying a $260 filing fee.

Meet with an experienced BK lawyer. You need to file a motion to reopen with notice to all entities involved. Then you need to amend your schedules to list the potential asset. Any lawyer worth their salt will charge you for the consultation and the necessary legal work.

You can reopen the case to add a creditor IF the claim arose before the day you filed the bankruptcy. You file a Motion to Reopen with a proposed Amendment listing the creditor, his address, the amount or estimated value, of the legal action, and the date when the cause of action arose. Courts charge $300 to reopen, and may charge an extra $30 for the amendment. Best of all, get the lawyer you used for the BR involved.