Also, my vote would be to hold the unclaimed stakes indefinitely. They belong to whoever bought them in the first place.
Yes, time shouldn´t be relevant, concerning owning rights ! !
I would create a random password as a key for the account and send them the password by bitcointalk. This way management can close distribution.
If they don't take it, its like destroying. And if they realize after a year, that they have a lot of money there, its nice.