Unlike MythBusters, SpaceX is likely to have more than one dummy and, unlike Nasa^H^H^H^HESA they tend not to make cutesy circus out of their projects, e.g. avoid things like "Oh, hai, Twitter, I'm the Rosetta probe! Yuppie!"
I don't think you're the target demo for the cutesy circus events. Unlike SpaceX, NASA needs all the public exposure and goodwill it can get, which is what the Twitter accounts are for. There are plenty of data and science-heavy websites for the non-casual user.
That's a quite myopic view of both NASA and SpaceX. The cutesy circus is pretty much a necessary condition of scientific popularisation-- NASA's social media experiments have been incredibly successful ways of getting the public to engage in space travel and science in a way that wasn't ever prevalent before.
It's trite, but also mandatory. I wouldn't be surprised if SpaceX didn't take some things tongue-in-cheek too; a war against humour is one nobody wants to fight. Except Boeing executives.
So I suspect dummies will remain anonymous.