I'm guessing algebra is difficult for journalists.
> Major investors, with lots of money on the line, also didn't catch this.
Major investors had all the incentives to keep the scam going as they stood to make big money from the scam.
Journalists should have the incentives to expose the scams, except they were not in this ( and probably some other ) case because they were either getting money from the scam or were trying to be the best cheerleaders possible in hope of getting money from the scam.