[IAmBatman]

C3G will be approving a scenario if it has its own map and we will definitely be putting each scenario and map through scrutiny unless they happen to be using a BoM map. But even then we'll be putting the map through scrutiny for how it works with the scenario.
Really, though, with the map usage being scenario based, we don't have to have the same type of scrutiny BoM or BoV have. We're not testing to see if the map works for competitive play - we're only testing to make sure the build instructions aren't flawed, the map actually stays together, and that the map works for the scenario (and that the scenario works in general). So it's really a horse of a different color. You could end up using a BoV map and while it's a great map for tourney play, it ends up being horrible for the scenario you create.