When my child was a toddler, she spilled her apple juice(?) on DH. That taught us to pack extra clothes in our carry-on not only for our child but for whoever would be sitting next to them.
About two years ago flying biz to AMS, early in the flight, I knocked over my white wine which was on the armrest. It luckily spilled all over on my neighbor's comforter and not on her clothing. I profusely apologized and offered her my comforter. She asked the FA and they had one extra comforter to give her.
Sorry for you it was tomato juice and the guy was a d-bag.