Newfag here. This article & Twatter thread enclosed therein theorizes about how Epstein might have made his $$. It's interesting that people have questioned the source of his 'expertise' and wealth for years, but are only now speaking out. One can only imagine the potential filth involved in this investigation.
http://nymag.com/intelligencer/2019/07/hedge-funders-have-some-thoughts-on-what-epstein-was-doing.html#comments