edit: another option is to appoint a proxy for Risto's accounts, IMO his 50% is too large to sit idle, someone needs to activate these accounts, either Risto or someone else
Yes, we were discussing on IRC newcorp which is part of his assets, though it wasn't immediately clear to me whether he is a majority shareholder or not. My suggestion was for the town to appoint a paid trustee to manage newcorp on behalf of the shareholders (probably with the choice of trustee approved by other shareholders). Appointing one to manage his assets more broadly is also likely appropriate.
If nothing else, protecting the value those accounts with reasonable administration will maximize probability and magnitude of the recovery to his victims.