I was just reading the info of Olive Garden on this site and decided to look more at the official website of Olive Garden to determine if they had anything vegan. They say nothing is "wholly vegetarian or vegan" depending on your beliefs and defintions. However, I found this Q&A about the salad dressing nutrition info:
"What is the nutritional content of your salad dressing?
Each two (2) tablespoon serving contains the following: 80 calories; 70 calories from fat; fat 8 grams; saturated fat 1 gram; cholesterol 5 mg; sodium 510 mg; carbohydrates 2 grams; protein 0 gram. "
My understanding is that all pure vegan foods do not contain cholesterol. This quote from their website indicates even the salad dressing has 5mg of cholesterol per serving and thus in my opinion making it non-vegan. Sadly, it looks like I won't even bother going to any Olive Garden as they just don't seem to be vegan friendly.