Using the opportunity made by her being distracted by the call to knock her unconscious...
And though she resisted slightly,
you somehow managed to stuff her into the car,
then after setting fire to the car, hurried back to the restaurant.
You changed back into your original clothes in the toilet,
then intentionally punched at me, a waiter, to injure yourself
and disguise the scratches she gave you.
Afterwards, you pretended to calmly call her,