When "nesting" goes wrong... An unfortunate series of events

Remember how I said earlier that everything was getting organized, including the garage, pantry, and closets? Well, guess where everything ended up that had any worth, but that we didn't want? The back of our Tahoe. I didn't want to throw it away, so I was going to take it all to goodwill or DI. Sometime. So when I needed groceries last Saturday, I had forgotten about all the stuff in the back and there wasn't much room for the food. A bagger helped me take the groceries to the car and I quickly put everything as much to the side as I could so there would be room for the groceries and then I put the kids in the car while she put the groceries in the back. When I unpacked the car I noticed somehow I was shorted a gallon of milk. I called the grocery store and they said they would replace it if I brought my receipt. Didn't do it because it was kind of late and I didn't want to make another trip.
Fast forward to Wednesday. After a while I noticed the car was a little smelly and I thought, "Braden, you stink!" I also made a quick stop to the store to grab car fresheners. Potpourri sounded nice so I got that one.
Then yesterday, Thursday, Jason was working in San Francisco and couldn't drive the truck because it is too big to park anywhere out there. He took everything out of the car: carseats, purse, papers, AND everything out of the back. He told me there was a weird smell in the car, there must be pee in the carseat or something so I handed him the potpourri car freshener I bought to put in there.
Thursday evening I noticed, sitting in the pile of stuff that had been pulled out of the back of the car, the gallon of milk in a grocery bag! The whole garage smells TERRIBLE. The milk is separated and leaking into the grocery bag. I called Jason and asked him if he noticed he had taken the gallon of milk out of the back of the car and he said he hadn't but he can barely stand the smell of the Tahoe anymore. He thinks we might have to strip the carpet and seats out because it smells so bad. I guess the hot day just did it in yesterday because when he got back and I smelled it, woooow it was not good. I think the potpourri smell added to the stench so I took it out and sprayed Fabreze. I let it all air out for a little while this morning but its still pretty bad.
Anyone have any great odor eliminating methods?

Oh, and just for the record... I SWEAR I checked though everything in the back 10 times just in case the milk was back there and found nothing. Jason looked too... and he didn't even notice he pulled it out of the back yesterday! Who bags their milk anyway!