I don't think there can be a governing body that is not de facto ruled by Valve. Most of the power within the Dota community is wielded by Valve, as they have unilateral veto power since they own the rights to the game and receive pretty much all of the revenue generated by the game and the competitive scene. They can prevent any tournament organizer they want from broadcasting their game.

Of course there can be a governing body that nominally checks Valve's power, but ultimately this governing body would only exist through Valve's benevolence. The power dynamic within the Dota community skews WAY too much in Valve's direction for there to ever be a governing body that can potentially defy Valve's directives.