I'm surprised they told you 7 working days unless it was for an itinerary involoving US sectors. The FAQ on the CX website have the below timeframes. In my experience, I've been told a refund could take up to 2 months, but usually gets processed in about 2-3 weeks.
http://www.cathaypacific.com/cx/en_H...on-refund.html
15. How long would it take to get the refund if I cancel my fully unused or partially used ticket?
After deduction of necessary cancellation charges, the residual amount will be processed in (counted from the day of receipt of the refund request):
7 working days for itineraries involving US sectors
6-8 weeks for credit card transactions
20 calendar days for ticket in other forms of payment such as debit card, etc.
Please note that the above guidelines do not apply to special refund involving service on other airlines. Time required for the actual refund to reach cardholder’s account will depend on the bank’s processing time.
16. How long does it take for the refund for booking changes made online?
The refund of the Online Booking Change transaction takes seven working days for ticket involved in US sector. Others take 6-8 weeks.