Dan PrimackIllustration: Sarah Grillo/AxiosThe most stunning part of the CaaStle fraud allegations isn't that a huckster CEO burned through $530 million, or that she appears to have forged years of financial disclosures. It's that the company's board let her stay in charge after finding out — and took months to warn investors.What follows is based on research and conversations with numerous sources:The whistleblower: Late last year, Jed Lenzner got some numbers from CaaStle that raised his eyebr...