I'm owed a $1350 refund from Travelocity, and I've gotten nowhere after two email conversations and 6+ phone calls. What are my options?

Update:

After getting my case noticed on Twitter, I was contacted by a priority rep from Travelocity. She was able to work through my case without me holding her hand (as I had to do with the standard reps), and I just received an email saying that a refund for the full amount requested has been processed and will show up on my CC statement soon (plus a small credit to my Travelocity account for the troubles).

Thank you everyone who commented with advice!

I used Travelocity to book my hotel reservation for ten nights. More than a week before leaving, I shortened my stay by two to eight nights ($496 * 2 refund). Before arriving, I noticed that Travelocity was charging me price for three adults ($496/night) instead of two adults and one child ($451/night), despite the correct counts being indicated on my Travelocity reservation ([$496-$451] * 8 refund). All of these changes were made within both Travelocity and the hotel's "no fee to change reservations" window. I should be receiving a refund of $496 * 2 (nights removed from my reservation) + [$496-$451] * 8 (difference between 3 adults and 2 adults+1 kid) = $1,352.

Math aside, I've had no luck over the phone or via email (where I was just told that I'd need to call to get a refund processed). What do people recommend for recouping the extra charges?