Yet another passenger side water leak

[kevineugenius]

I went over the TSB, looked a bunch of videos on Youtube, read every forum post I could find and so far none of the "common issues" seem to fit what my car is doing. 2007 GT Coupe, this is only the second time that the carpet has been completely drenched. The snow last week didn't seem to bother it, but rain in quantity sets it off I guess. Both front and rear passenger footpans (feetpan?) are wet, front moreso than the rear. There's a rib under the front of the seat, so I sort of assume that to mean the leak isn't under the dash like most people's are. I understand water can crawl across carpetting to some extent, but I don't know what that extent is. The car is white, so I first checked for dirty areas inside the weatherstripping thinking to myself that dirt would probably accumulate where water is present. There's quite a bit to the rear of the doorjamb (on the body side, not on the door) and there were water droplets all over the door sill plate, bottom of the door, and about 6 inches up the jamb on both front and rear. Some of it looked like condensation at the front. The carpet is of course wettest at the lowest elevation points, but it does seem damp up by the front kick panel, though when I removed said panel and pulled the carpet back, I didn't really get any clues like dirty spots or extra wetness to say where it might be coming from. At the behest of some Youtube vids and the TSB, I popped the passenger cowling loose and checked the grommets and cabin air filter area. The filter is bone dry and the compartment it's mounted in barely had any dampness at all, so I'm guessing the drains aren't plugged. Grommets all seem seated properly, cowl is not warped or cracked, and none of the weatherstrips are cracked that I can see either. I also don't think the drain hole plugs at the bottom of the door are the issue, but I suppose I could pull them out just in case (have not done so yet). My best guess is that where the body-side seal and the door-side seal come together at the rear bottom corner of the window something just isn't sealing all the way. However, replacing both strips is like $200 and I am in no situation to drop money on a whim. I'm sort of wondering about like an adhesive-backed rubber shim to just make that section of the seals a smidge thicker, but I don't know of the existence of such a product. Have I missed anything?