I'd have thought that lye based alkalais would help remove the oil. Oil plus alkalai turns into soap. That's how oven cleaner works. Actually, I would have tried oven cleaner.
Battery acid.... dangerous.
When I was a kid, my Dad told me his battery acid story. He was over at a friends house. They went to the cellar for soemthing, and he absentmindedly sat on a car battery. Two days later, the seat fell out of his trousers.
One friend of mine had a battery blow up. He was using 12 volt boost setting, and went to wiggle the battery clamps. He got acid in his eyes. I grabbed hold of him to go in the house and wash his eyes out (lucky, he can still see). I had a prompting of the Spirit to wash the coat in hot water and baking soda. Didn't think I got that much acid on me. Well.....I got enough acid on my coat, the front fell out pretty badly. I still have that coat. Shoulda thrown it out, years ago. I keep it as a reminder to heed the promptings of the Spirit.