Their most valuable is an active elder who is rich and retired now who is also a married brother, and he and his wife are pioneering (or otherwise involved in what they call full-time service) and this childless couple (with no relatives to leave in their will) dragged many people from the territory into the hall to the point of baptism. Further, those people they dragged in are also active and holding positions in the congregation.
Regardless of all that, he is only worth what he is willing to do next.
Because of his money, they will try harder to retain him if he produced "doubts" but they would still drop him like a hot radioactive potatoe if he stirred up trouble with those doubts.