I had a similar, but not quite the same, problem a year ago. I booked a revenue flight for a minor family member and his mom. I used the bane we all call him, which I thought to be his legal name. We decided to create him a skymiles account after booking. His legal name, used to create his SM account, and the name I used on ticket were slightly off. I called and they were able to correct the ticket without problem at no additional cost.
I've also seen where AFKL will add MR/MS/MRS to ones last name on the reservation but it's never caused a problem with TSA or Delta.