Steam-Dependency Failure

I recently bought the Steam pack for Orcs Must Die 1 and 2 along with all their downloadable content. Orcs Must Die 2 starts up just fine, but when I try and run Orcs Must Die! it goes from the preparing to launch to a Steam Error message of…

“This game is currently unavailable ( Dependency failure)."
 
I’ve tried reinstalling the game, verifying the integrity of the game cache, and browsing google for any proposed solutions. So far the only fixes for the same error in other games (I find no mention for Orcs Must Die!) I find do not fit with Orcs Must Die! (downloading a game specific file from the Tools section, waiting for other parts of the game to finish installing, etc). Any help would be greatly appreciated! Thanks.