I can't really feel sorry for Stu though. Being that slow and having that much [inherited] money is always dangerous. He's lucky he's in it "only" for ~$20m. It probably wouldn't bankrupt him but may make retirement with Elise less enjoyable.
I don't know how anything in this saga could shock me, but I would really be shocked if someone who became a VP at Cantor was able to get fucked by a peon like Garza.
I can see him conning Stu out of some money, but leaving him holding the bag of all of this is crazy.
Perhaps he got into Cantor via family connections... so maybe not quite an uber-smart self-made entrepreneur. Plus greed. There is always greed. Dreams of being the next Bill Gates or Elon Musk.
http://www.nytimes.com/1996/04/28/business/with-partners-like-these-who-needs-rivals.html
Homero was good friends with Uncle Stu's son. that's how they met. i can't remember where i read that, but it's true.
i imagine garza's mom probably cleaned the Frasier's toilets and their children ended up playing together.