That would support the notion that Du Val promised to convert and issue stock to other parties and never did.
(these links are all empty apart from a logo and a date ranging from 2013 to 2016)
What's especially interesting and radical about this is that, if it's true, the note was no-recourse for the investors. As I imagine is typical, a note I did once would convert to preferred upon raising a certain amount of money, but if we didn't, the note holder could either extend the term or elect to take common instead. The idea that you could do a note where the investor gets nothing if you don't raise more money is fucking wild.
That said, I guess it's not totally beyond the realm of possibility that even investors like A16Z would consider doing a no-recourse deal, provided the round was really hot and the investor was super confident that the company would raise more money.
If it's true that the note is no-recourse, then I say more power to him. Ask for the terms you want! You'll never know how much leverage you really have unless you try. The worst thing that can happen is they say no.