Sorry to hear about your damage: it's borderline immoral not 'fessing when you've done something like this - and doesn't that count as "leaving the scene of an accident" and therefore actionable on that basis?
I know how you feel though - I've had my car (the Tesla, not the S8, thank God...) driven into three times in the year I've had it
. In each case I was parked up and either in or next to the car, and with witnesses, so luckily no question of who's fault it was, but it's still traumatic and a ball ache to rectify.
Hopefully you'll get a result soon...