First, I'm so terribly sorry for your loss
and I'm glad you were able to get confirmation that the food was not the problem so you have peace of mind.
Just to add to the post regarding if there is any danger to using Nature's Variety Raw - I fed my dogs and cat NV raw, kibble and canned(including chicken) for 2 years and never had any problem. Many of the things that would make us sick dogs' systems process very differently. (only dogs that have some sort of immune compromising condition can be effected by salmonilla). The vet I worked for for many years who's clinic was certified by AAHA and did constant furthering education in canine and feline nutrition recommented a raw or partial raw diet for every patient and made his own raw diet for his dogs which included NV as well as other raw meats (even venison that he hunted himself). He was so impressed with Natuer's Variety's nutritional content that he started selling it instead of Innova. My experience is that NV is a wonderfull company that does major research and quality controle and feeding raw food to dogs is safe and very healthy and natural for them