After watching the video you linked and recalling when I smell the stink, do you think it's possible that the bad smells are coming from the aero shield area where the drain hole pours to? I only get the smells after the fan stops blowing for 15-30 minutes. Looking at the video, it doesn't look like there's much decay or bacteria growth in the coils/filter area. Maybe the bad smells is back flowing through the drain hole from the aero shield area whenever the fan is off? The car honestly doesn't smell bad at all while the fan is running, it's always just a blast of sour smell for the first 30 seconds or so of turning on the car.
That’s what I’m thinking, either on top of the aero shield or maybe in that hole where the liquid drips out of. I just have a hard time believing it’s 100% the filter, or 100% the coils. If it were, I’d expect it to be more persistent and not just go away seconds after turning the AC on.
I tried an experiment where I mixed Lysol from concentrate and slowly poured it into the intake vent so it would run out of the drain hole. It ran out of the bottom of the car like you’d expect and I heard it hitting the aero shield. I’d like to say it helped but I'm not 100% sure because I changed the filter and did the coil cleaner a week later and the smell was faint to begin with. I’m pretty sure there was no smell for that week but I can’t say for certain. This was all in January and I’ve been odor free since then. If it comes back Im going to try it again and see if it works.