The way I see it, Musk is only going to provide the investment if it fits into his investment portfolio strategy. With $2 billion, I would give $1 billion to charities, and the other $1 billion I would use to purchase as many American Southeastern coast beach houses as possible. I would sell the beach houses to climate denialists at half-off, instantly losing $500 million in the process. I'd keep the $500 million from the house sales to myself, because Musk knows that some money has to be kept to keep the lights on. The purchasers of the houses would slowly watch as their new investments into their houses literally goes into the ground (er, or oceans, as it is in this case).

I figure Musk can't resist an offer this good. My genius then continues to go unchallenged, except for Musk, who can somehow tank investments faster than this.