I didn’t see Carson’s sketch or Dunham’s. I don’t know if she was actually mocking God or the Bible. A lot of the humor — if that’s what it is — seems to be directed at her show and the character she plays on it. Her boyfriend on the show (or the actor who plays him, or both) is named Adam, so the sketch pretty much suggested itself. It looks like they were sending up the wave of Biblical films to some degree, but Adam and Eve isn’t really hardcore biblical material, is it?
I agree with you re the skit parodying Girls itself, but showing how insipid these characters are probably went over Dunham’s head.