Your post sparked my curiousity however and I will ask my Dad about Grayson.My Dad was b. 1938 in Louisville but his sister married into the Mullins family who hailed from Grayson.
He used to drive down there with his friends ALL the time when he was young.His friend's name was Grayson Mullins.I will ask him about the lost town.My Dad got stuck in the mud on the way home one night from there, caught pneumonia after pushing the car 3 miles through the mud in the 50s.I will see what I can found out for you about this town.
Also, you might check for an earlier marriage of your female ancestor.I have a lady on my maternal side, her marriage was listed with her widowed name not her maiden.I found the first marriage and found her real surname. I was searching for feverishly for a woman named "Bennett" and it turned out her maiden name was really "Owen".When she married my ancestor, she was Bennett but not at birth. :)