That’s pretty much what Theranos did. The due diligence people walked away and threw a few hundred million more at Theranos. That’s compares to the due diligence we went through when I worked at a small startup years ago. It was only for a few million but they made us go through hell with all their information request.
Seems if you want to commit fraud it’s best to go really big. The bigger you are the less scrutiny and less consequences.