Good luck, I hope it's somewhat legal where you are. I don't see anyway possible with a neighbor above you to grow and dry weed without them smelling it at some point. I hate to even make a recommendation how to fix any smell issues because I don't want to encourage you to do something that will get you locked up. But I will in case you try to do it anyways. The best smell control comes from having negative pressure in this case in your lung room( rooms tents are in). Leave your carbon filters you have in tent in the tent. Get another carbon filter and vent it out the hole you were using for the portable ac. Let it run constantly. When you vent back into the house it works okay til mid to late flower but it only removes about 99 percent of smell but that 1 percent builds up over time and you start to smell it throughout your house. Thats why you need to vent the room the tents are in to the outside through another filter.
I'm still not so sure that you can pull off growing weed with neighbors up stairs that are not cool with it. When you leave tent doors open that makes those filters less effective, when your drying its really hard to control the smell. I can't tell you how many times I had to leave work because my clothes smelled like fresh weed, and that was just from being in the house with drying weed. And I had all kind of carbon filters going.
Also if the power goes out for 15 mins in late flower your whole place and theirs is gonna stink. You could smell mine at the curb when it happened and it was Halloween so all kinda of kids were about to be out walking around, had to go buy a generator.
Also just cause you can't smell it doesn't mean they cant, your just used to the smell. You can kinda see what I mean if your not home for a long period of time then come back. But to someone who doesn't like the smell it's gonna pretty obvious smell.
Those portable ac blow smell right outside btw.