Money not fully paid

My father was working for Middleburg Mine and registered under Mine Workers Provident fund, He past on 2007 three of his children were registered as beneficiaries but only two of them did get some compensation of which the third child disappeared 2005 and his no where to be found. Its It's been thirteen years since my my father past, what's happening with the money that was not paid out. Every time you phone the fund there is no straight answer.