Agreed someone will have to get a court order or new custodian to take over the stock to get it out from greys. No chance of this happening a/s blows that away.
You are correct about SEC suspension of trading. However, if FINRA suspends the cusip, then I think the stock is gone forever. That deletes the ticker. I have tried to lookup cusip suspensions, but I have had a hard time finding clarification on that issue.