Going ahead and assuming (yeah, I know) it was Petco's fault due to coincidence.
http://www.providencejournal.com/news/20170327/rispca-investigates-death-of-pug-at-middletown-petco
http://www.providencejournal.com/news/20170327/rispca-investigates-death-of-pug-at-middletown-petco
MIDDLETOWN, R.I. — The R.I. Society for the Prevention of Cruelty to Animals is investigating the death last week of a pug left at the Petco in Middletown to get his nails clipped.
RISPCA President E.J. Finocchio said the body of Ollie, a 16-pound, 5- or 6-year-old pug, was sent to Tufts University for a necropsy that he hoped would determine, by the end of the week, how Ollie died.
[....]
Ollie had had his nails clipped many times at that Petco, and he said veterinary records showed the dog had been in good health. Possible causes are a medical crisis or strangulation by the loop that limited his movement on the grooming table, Finocchio said.
Petco had not yet responded to RISPCA requests to interview the two technicians, he said.
A corporate-level statement from Petco said, in part: "Despite public reports to the contrary, the attending vet has confirmed that there was no overt evidence of trauma or neglect...." [....]