This is heartbreaking but I don't believe it's the treats. There are far to many small dogs my two Chihuahua's included that get these treats daily and have never suffered any health issues from them.
Here's a list of what can cause Renal Failures in Dogs
$1:
Causes of acute kidney failure include:
Complete urinary tract obstruction caused by a stone
Rupture of the bladder or urethra
Shock, with inadequate blood flow to the kidneys
Congestive heart failure with low blood pressure and reduced blood flow to the kidneys
Poisoning, especially from antifreeze
Lyme disease
Leptospirosis
My guess is that the dog got into something else or had an outstanding health issue which because of the previous scare about this product it automatically became the Vitalife's fault by default, again.
So, unless this Vet can definitively do what no one else could and tie the jerky treats to the death of this dog and the dogs previously she should STFU and stop scaremongering because given that other outlets sell the same products all the accusations against Costco are doing is making it look like one vet's got more of a hate on for Costco than any concern for the dogs.
She'd be better served taking the leftover duck jerky treats to a reputable lab and having them analysed for toxicity levels before making statements that are so inflammatory which makes me wonder why this hasn't been done in this case.