I would still look for a way to vent out of the attic. Even if you had to go up there with a hole saw or a drill and perforate a 6" hole . I would think that Blowing into the drywall, the smell will still permeate out somewhere in the house.Well I finally went up in my attic and there is no gable. One small window but no sorce of vents or anythign to tie into. On top of that I live in a twin and the dividing wall is so thin I can see in my neighbors house through the cracks so bad smells up there would be a bad idea.
So I am thinking again of cutting a hole in the dry wall and blowing into the wall. I will need to make an intake though that goes into my bedroom which has A/C. How do I make an intake vent with out letting abient light through the vent that would screw with my dark cycles?