My question involves criminal law for the state of: Illinois
For extra context, everyone in this situation is 19 and in college. This was during spring break. This happened during the nighttime at around 9pm.
Over the weekend, I saw one of my friends driving in his car. I was behind in the right lane, while he was ahead in the left lane. When I recognized it was his car, I sped towards him, and rolled down my window. I yelled his name, but in the coming seconds, I was surprised when the passenger threw an egg which landed inside my car. The egg yolk went all over the interior of car which included the windshield, cover for the instrument panel, driver seat, top of the dashboard, center speaker grille, as well as my Northface jacket and jeans. I was completely shocked and utterly frustrated. Not to mention, I was driving in my prized Mercedes, which I take the utmost care of. I had my friend who was sitting in the passenger seat, call the friend who was driving the car, and I began to rant and threaten to call the police on him, if he didn't pull into the nearby gym parking lot. They came right away and began excessively apologizing. They told me they thought I was someone else that yelled "f**k you" to them at a Walgreens. Either way, the actions were still unjustified. I was more than ready to get the police involved in the situation, but since I knew both of the people in the other car, I didn't. For the next 90 minutes, they attempted to clean my car, but it wasn't as clean as it was prior to incident. The next day, the egg thrower and I agreed to a restitution that included payment for a full car detail ($200) and dry cleaning for my jacket ($5).
What I'm wondering is did I handle the situation properly? I'm researching vandalism charges and I found out that intentionally vandalizing property that exceeds the value of $500 (the Mercedes easily exceeds this) is a felony. If I called the police, would he be charged with a felony? How would the situation be handled differently if the police were involved.

