Again, Tesla wanted to make believe (or maybe they believed it themselves back then) the public/investors that this $2 billion round would finance the Gigafactory. It didn't.
The latest 10-Q states that only $261 million have been invested so far and the RGJ article linked above even uses a lower number: $238 million.
In any case, that's a fraction of the full investment needed until 2020 while the full $2 billion raised are already spent (obviously mostly on other purposes).
PS: This article makes a good analogy with the nascent solar market. Being the "biggest" player early on doesn't garantuee success, far from it because of technology gaps in the future:
Could Falling Costs Be a Bad Omen for Tesla Motors' Gigafactory? -- The Motley Fool
Remember when Q-Cells was the biggest solar manufacturer in the world and poised to dominate the panel industry for decades thanks to economies of scale and advanced tech compared to Asian competitors? That was just a few short years ago...
Margins for all kinds of batteries have been equally razor-thin for years. Just because a new sector has exploding revenue (see solar panels, flat-screen TVs, flash chips and computer chips as recent examples...) doesn't mean op margins are good or early leaders won't be toppled by fast followers with deeper pockets.