Investigators said 16 dogs were in kennels and many were covered in their own waste.
"They were all 10-15 pounds underweight. They all had muscle mass loss and dried feces upon them," said Diane Franklin, the director of the Whitfield County Animal Shelter.
Police said Kinder later shot himself to death Thursday afternoon.
Abigail Eastburn said she took her English Great Dane to the center -- and when her dog came back, he was 30 pounds lighter.
Eastburn said her puppy Duncan is an 8-month-old and that two months ago, he was energetic, and a “big goof."
"He was brought up in a good, loving home, so he just now is completely different," Eastburn said.
She said everything changed when she sent him to stay with Kinder, who she found on Facebook, for seven weeks.
"The price appealed to me. They had good reviews," Eastburn said.
But when she finally got her dog back from Kinder Dog Training, she and her mom knew something was seriously wrong.
"I was heartbroken," Eastburn said. "He had diarrhea, vomiting, was lethargic. He couldn't walk. He was falling asleep standing up, and was kind of tumbling over."
Eastburn took Duncan to the West End Animal Wellness Center, and doctors said he will recover but has a long recovery ahead.
Duncan's family just wants to move forward with a new mission.
"We really want the negative that has been surrounding the Duncan story to turn that into something positive," Eastburn said.
Duncan's family created a nonprofit named after their puppy, called Duncan’s Voice.
They want to use it to advocate for dogs and their owners and get more regulation concerning the treatment of animals in Georgia.