I'm fairly sure that the starter motor is fine. I've cranked the car a couple of times since this morning and it's functioning properly. I just screwed up my timing this morning.
I crawled under the car and felt around. There is definitely exhaust leaking out of the rear cat. It's also pretty beat up from my many rally adventures. I may have punctured it. My current plan is to remove the pair and gut the rear cat, hoping that the clog falls out with it. I really hope that the O2 sensor is fine.
Wish me luck.