The misfire may be nothing more than a bad spark plug or plug wire/coil pack, but I wouldn’t expect a misfire to immobilize the car. Let’s just hope the dealership you bought it from knows Audis so you don’t fall into a rabbit hole of “well, if that doesn’t work, we’ll try replacing the chronosynclastic infindibulator.”
Audi A4: the coil packs are a well known problem. Make sure all of them are replaced, and take the car in immediately if the problem recurs. A misfiring plug can ruin your catalytic converter-that’s about a $1200 item on your car.
Not sure, I’ll be asking them about that when I pick the car up. If the shared cost isn’t too much I’ll just shrug it off.
oh, you bought a used Audi.
best of luck.