Thank you all for your advice.
I think that this may have been a blessing in disguise for the family. My mom also takes care of her mother with dementia while working a full time job, so not having to worry about a diabetic dog anymore is a relief.
I emailed my Dad and told him that we should definitely wait and see how she feels later on. My mom always gets in a "mood" and we know what she wants next by what she's browsing the internet for at night....i.e.: a new car, a lakehouse... maybe a dog will be on her list sooner than we think.
Scruffy is now in the freezer at the vet, awaiting the arrival of his casket that will be buried in my parents' backyard. As inappropriate as this may sound, I'm glad he has a lot of fur to keep him warm.
