CHICAGO (CBS) — After 30 dogs died in a fire at a kennel in the west suburbs, records and video obtained by CBS 2 show that DuPage County had investigated complaints against the kennel operator, ranging from overcrowding to mistreatment of animals.

RELATED: Questions About Whether Kennels Should Always Be Staffed After West Chicago Fire Kills 30 Dogs

A former client is speaking out. She’s one of the people who filed a complaint against the kennel operator before the fire broke out.

Startling video taken by a DuPage County Animal Control officer from an inspection over the summer shows a dark apartment filled with crated dogs. Many of the cages are stacked on top of each other with dogs barking loudly.

In an email from a May 2018 exchange between an animal control officer and the Department of Agriculture, the officer said the smell inside the kennel “could only be described as rotting/decomposing smell and it was nauseating.”

“I even looked inside a dumpster fully expecting to find something deceased,” the officer wrote.

The only source of light was reportedly a strip of Christmas lights hanging from the ceiling.

What’s significant about the report is that the majority of the dogs who died in the fire on Jan. 14 were inside the apartment unit, trapped in their crates as the flames took over the building.

CBS 2 spoke with kennel operator Garrett Mercado that day.

“You do what you can and hope you can save as many as you can,” he said.

But Terri Crotty, a former client of the kennel, wonders if the tragedy could have been prevented.

“If all the complaints and all the red flags were listened to, maybe we wouldn’t have had that,” she said.

Crotty filed a complaint with DuPage County Animal Service a year before the fire.

That’s when she picked up then 2-year-old Magoo from his 35-day stay at the kennel facility.

Medical records show Magoo had lost about 10 pounds, was dehydrated and was covered with open wounds. Crotty said she knew the experience might be stressful for Magoo, but the kennel operator never contacted her.

“I was never informed that Magoo was losing weight. I was never informed that he had puncture wounds or whatever the wounds are,” she said.

Crotty runs her own rescue in Plainfield and speaks from years of experience working with dogs.

She filed a complaint, but despite Magoo’s story and other complaints about overcrowding and the conditions inside the apartment “The Bully Life Animal Services” remained actively licensed by the state. It passed an inspection in the fall.

Crotty thinks it shows a loophole in the system.

“I started speaking out in 2017 when the incident happened with my dog,” she said. “It should have stopped with my dog.”

CBS 2 reached out to Merdado but did not receive a response. A GoFundMe page for him raised $93,000 from more than 2,000 people following the fire.