I was not aware of the $100 EACH WAY surcharge until getting to the ticket counter (after the round trip ticket was paid in full). I wrote a complaint to Delta who's boilerplate response was that it was standard operating policy to decline waiver of this fee.
Although I informed Delta at time of purchase of the minor and they took down all contact information about who would meet her at the destination airport, no mention was ever made of an additional charge upping the ticket price by over 60%. I had checked on a ticket by American who mentioned this fee and I chose Delta because there was no mention of this fee when booking the ticket. Why wouldn't they add this charge when I paid all the other charges with the ticket purchase? Nothing on the itinerary even mentioned this charge.
Delta took no responsibility for their poor communication and SOPs. I will always look to alternative airlines and not fly Delta in my future travels.