General tip, if you want free advice, it's going to cost you at least a minimal amount of patience. As to your question, the best answer I can give you is maybe. First issue is airflow. Is your fan able to push air through your filter with enough speed to ventilate your box? If so, you also need to make sure it's not too fast, as that can leave you without enough time for the carbon to do it's stuff. As to whether or not it will control your smell, that depends on even more factors, again the best I can do for you is maybe.
yeah its going to depend on the airflow like horticultureFTW mentioned. ive always recomended putting the activated carbon into a bucket with the hose going thru the buckets lid, with holes drilled in the bucket to let the air flow out but its deff going to be better than nothing.
Well, you can test the airflow easily enough, just turn it on and get an idea of how much air is moving through the filter. Off the top of my head, I can't think of a way to know for sure how much smell removal potential you have until you've got some flowering plants in there.
One other thing, the smell is going to build up slowly as the plant matures. What you could do is have a backup plan in case your filter isn't enough. If you make it a point to smell the air coming out of your filter every now and then once flowering starts, you should be able to notice if your filter isn't keeping up before someone else does.