Keep giving him long mistings, as long as you can manage, especially to give him a chance to rinse out his eyes well.. His Cham will probably be okay. It was an accident. Check the packaging for any directions for skin contact. If the shoe cleaner is greasy or has oil or silicone, you can use a very soft cloth and warm water with dawn or ivory liquid dish soap (just a little) to help clean off the skin. Be gentle and rinse really well.
For the future, chameleons usually don't need any products to help them shed. Extra mistings or raising the humidity is usually all that is needed. That will save you and your brother some money and avoid this accident in the future. Good luck and keep and eye on the cham for a few days.