This was well known among JW insiders here in NYC. How they got the money always made me wonder. There are the green handshakes, and there are really very few controls for people in positions of responsibility to siphon off money. Its also possible that while they invested they may not have done so in large quantities, though the way they used to brag about their investments leads me to think at least some did have substantial funds invested. It should also be noted that some Bethelites in high places had jobs on the outside before coming to Bethel and so could have obtained money that way. Some are even retired, collecting their pensions and living at Bethel. Those guys really make out as Bethel pays their room, board and food while they collect a real pension from their days working on the "outside".
BTW-I searched the WSJ document for addresses in Brooklyn Heights. One came up but I didn't recognize the name.