I got to pick up Buster and got home a little after midnight. The doctor said they had to pretty much open the entire incision. They cleaned it out and cut away the bad tissue and then "laced it up". I need to call my vet when they open and then take him in daily until they can close it. After it's closed, he'll need a drain to help it heal properly.
He was still coming out of anesthetia when I picked him up but he seems to be feeling ok this morning.