Set ithe domain up for auction until it's time for the domain renewal.
You never know who may want it and it will be "advertised" when up for auction.
If, my post was helpful would you please mark it as helpful or 'best answer'? - Shameless plug, I know :)
Anyways, I hope this all works out for you. You should be set up for closure and by keeping your certified mail rec'ts you cannot be sued in civil court and or it wont stand if someone attempts to sue for lack of notice.
Although we live in a digital age a certified rec't is usable in a Court of Law without reproof. Emails can be reproved.
I wish you the best!
Let me know if there's anything else I can do for you.
Thanks Mark.
