Despite TURNA's poop and puke concerns, I decided to give the Home Depot carpet machine a shot. I also used Tide, Dawn dish soap, and some citrus degreaser with similar results to the Spot Shot and scrubbing. I used Zep carpet extractor shampoo at about 10 parts hot water to 1 part Zep, and a bit of Dawn. It definitely worked and was really good for saturating the carpet with the shampoo. The only thing I didn't like was that it leaves the cleaning solution in the carpet. So I used my old Honda pressure washer on the lowest pressure with the widest nozzle to rinse them.
The carpets don't look brand new, but definitely as good as they will ever be. I don't really have any before pictures, and I'm waiting for them to dry out to get some after shots, but here's a video of what got sucked out-
Ew. Between the carpets, the front seats, and the bottom rear seat cushion, I probably pulled out 6 gallons that were just as dirty. I'll get after shots as soon as everything is dry.