You can seal all the seams except for one window, which you would leave open. Get a garden hose and a bunch of really strong friends, and use the Ilford washing method
Anything that can be physically removed from the car, remove and wash - and dry well. Anything that you can't remove, like seats or carpet, may be difficult to get completely dry, and that can cause problems in the future. So be careful how wet you get them.
I would start conservatively, and you have some good ideas in this thread already. Treating it like a pet "accident" may open some options, so a pet store may have something good. You could also talk to people who detail cars, as they may have suggestions.
Basically, you are cleaning (though the chemical smell may be more difficult than a visual stain). My grandmother used to be able to clean stains a dry cleaner could not take out. Some of it was more "folk" remedy, like milk or baking/baby powder - and in that respect, the cleaning media may or may not have been effective. What I think worked most for my grandmother is that she was a very patient person. She kept at something until it was clean (she was a bit OCD in that respect). She didn't care if it didn't work all at once. A little progress each time was enough.
So, you may be best served by
repeatedly using whatever method(s) you choose. A few times a session, a session every day. Just keep at it.