FSK Audi Attempt to sell new battery when battery is not needed and customers battery was run dead by Audi service personnel Frederick Maryland

In late October I went to pick up my Audi at FSK Audi. It had some work done on it already, I paid the bill and went to get into my car. The battery was dead and the headlight switch had been left on. One service person went out (I didn't follow and observe), he comes back and says the battery is dead and won't hold a charge so I need a new battery. The battery in the car was only a year old or so and I'd never had problems before. At first I go along with the c**k and bull story but then change my mind. When I tell the service person I didn't want a new battery, he thrusts the car key at me as if to say, "Ok, go ahead, what are you going to do to get out of here without our new battery?" I get a manager and he goes out to jump the car. This time I walk out to observe, and the manager gets into the car and the car starts up no problem. So, why did the first service person say the car wouldn't turn over? Both service manager and the cashier told me, "It's been cold, the battery is dead and it's an after market battery.." blah blah..
The manager also was trying to say he'd have noticed if the lights were on. So they were also calling ME a liar.
I hopped in the car and drove away, there's been no problems since, the battery is fine.

Stay away from FSK Audi.

Engineer
Frederick, Maryland
U.S.A.