See, I'm kind of mixed here: On the one hand, I don't really feel like we'll actually be making use of her capabilities or fighting LexCorp any time soon. On the other hand, "the number wouldn't hurt, and if she's acting as a freelancer, we might be able to pass the number onto the boss, with the understanding that this is someone who can help him gather information, but is also a thief, so watch be careful with when you call her".
Then we can let him decide whether to use her as an under-the-table asset for his running around in a suit beating people up. I can understand why people would choose to Refuse, though.
[X] Accept - (Gain Catwoman as an asset for corporate espionage)
Basically though, my stance is "take the card, but hand it off to the boss, see if he wants to use it".