Follow the money.
Appraisals permitted the lenders to loan based on presumed security. The amount loaned appears to be triple the true market value. Since it is unlikely that property values in that area have varied dramatically downward recently, only a fraudulent appraisal can explain that.
That means that the seller, who probably obtained the properties at the lower market value sold them for triple their value and pocketed the money. This fraud is not about lender's fees. It is about fraudulently inflated appraisals.
Unless it was the broker who "tamperd with" the appraisal values. I'd wait to judge, since it's the broker they're trying to find and the appraiser is still in town.