Nah.

It's probably more so that if the scam artists can convince a few members of the congregation to go in on it, their interpersonal relationships and religious background ("They'd never give me a bad deal") will keep anyone from looking too closely at it, and of those that are skeptical, they're probably not going to say anything to the FBI or secret service because they don't want their friends or church leadership to lose all their money to an investigation or attract unwanted attention from people aware of the sudden financial windfall.

Given the reports that people were told to keep it "hush hush", I'm guessing a few knew the money wasn't legit but went along with it anyway because they were profiting off it at the time, and too much oversight might damage that income.

It wouldn't shock me if MLMs targeted any closely knit group that could give their scam a sense of legitimacy.

e.g #girlboss and the terms affiliation with MLM schemes targeting women.