Here are the pics. A little hard to see, even in daylight but they are definitely there... What do ya think? I read that people use baking soda often for this type of oil but I'm not sure how that would work out in a car..
I would start by spraying some upholstery cleaner such as Folex on it, agitate it a little bit with a brush, and then vacuum up as much as you can and pat the rest dry with paper towel. If that doesn't do it you may need to have the seat steam cleaned.