There is civil fraud and criminal fraud, which require proving the same things. But generally, the government will only pursue criminal fraud prosecutions when there is a public interest component. Madoff defrauded a large number of people, and his fraud affected little old ladies' pensions. The government will generally stay out of fraud directed at a handful of sophisticated investors.
It seems like clear fraud was directed at the general public and their health outcomes. I don't care much about the investors, they can take it. It was something like 6% of tests were fraudulently performed by their "technology", with potentially dangerous results.
