Need help - Tint guy left car on and battery died




I took my GLC63 to get my windows tinted, and the tint guy (although I trusted the dealer I took it to) messed up. He left the car on (not engine running but electrical system on) all day to roll the windows up and down.
After I drove away, I got a blind spot assist system inoperable warning light on the dash and the system didn't seem to be working on the highway. I called the tint guy and he told me he had never seem that before, but that the batter had died because he accidentally left the car on all day. He told me he had to jump it with a jumper power box.
I'M PISSED but luckily the owner of the shop is a good friend and wants to make it right. He is gonna have the car checked out by a MB dealer to test the electrical system.
Obviously it isn't good for the battery to be drained like that. Does anyone know if that would have caused long lasting damage to the battery or diminished its life at all?? Should I fight for a new battery to be paid for?
Thanks in advance for any insight/help.


