Wierwille couldn't have cared less what happened to TWI when he was gone.
He put the family farm in the name of TWI, so all the improvements could be paid for by the organization, and he would pay no taxes for it. It didn't matter that his children would never inherit it.
His Board of Trustees was made up of the minimum number of people it takes to be a nonprofit (3), making the Board easier to control. He didn't want strategically-placed individuals, mighty in the Scriptures, or even lawyers or accountants, like most nonprofits. He wanted yes-men who would let him do what he wanted.
When it was time to "pass the mantle," this leader who proclaimed the importance of the ground-breaking research he was doing didn't choose the much-respected head of the Research Department to succeed him. Instead, he set up the two biggest tushy-kissers, one in Europe and one at home. Craig was his mistake, because Craig couldn't wait to grab the throne and minimize Wierwille's influence while he was still alive. So Wierwille turned to Gartmore for adulation.
When he was alive, he drank, overspent, used, and screwed his way through as much money and humanity as he could. He almost lost the whole thing when he forgot that one of the few things he shouldn't do as a nonprofit was endorse a political candidate. But he could promote or discredit just enough people that his indiscretions were never revealed to the believers at large. It took the Internet to do that.