I was rewatching Mad Men lately and it reminds of Peter Campbell. Early on, Peter screws up something badly and Don wants to fire him, but he can't because the firm owner Sterling explains, Peter comes from a wealthy family and his family connections bring business to the firm.
Sounds like maybe the same thing? Even if Zach Dell just sat a desk and stared at a wall all day, he'd probably be invaluable because his father is a billionaire and he knows other billionaires and he can introduce them to the principals at the firm.