Hopefully you won't kill me for saying this but it looks more like self inflicted parking damage to me than deliberate vandalism. Seeing as it is a passenger side rear scrape that you only noticed when you got home are you sure it was definitely done today? The sort of cunt that keys a car is usually a pedestrian so I wouldn't expect the two things to be connected either. It's going to piss you off forever knowing there is damage there but the bumper damage looks like an easy repair for a mobile bump and scrape fixer if you have one local to you. Key scratches can also often be sorted by the mobile man too or if it is only the surface one of the detailing mentals off of
detailingworld or a similar american based forum may know someone local enough to you that could get rid of it.
Getting your insurance to fix it will cost you higher premiums for the next 3 or 5 years as well as any excess that you have to pay so I would definitely be getting quotes to fix it before deciding on going through the insurance.