Oooh, just watched episode 3 and may well have to review episode 2 as well...
Anyway, after reviewing the car park scene:
She arrives in the van with the girls
The other man approaches from further up the park
They exchange something
She says goodbye to the girls
The girls get in the van with the man
She flicks the lights on the car.
She goes in (presumably the toilets) - female toilets are often two cubicles at least, but who knows...
Quinn approaches
Veiled woman leaves
Quinn notices veiled woman flicks the lights of the same car
He follows her...
So, my take is: the other man was in the car, got out and gave the woman the keys, she locked the car as she was going in the toilet, goes in and then out (pretty quick change, btw) and unlocks the same car, making Quinn change course. Nothing particularly odd or leading to suspect a bomb.