LTS, it sounds like you were married to a very cruel person. But I guess that is the Dubbie way, no sympathy. My husband's family (notJW) have a motto; If you are looking for sympathy, you will find it in the dictionary, it's between Shi* and syphilis.
I guess that is why I wasn't a very good JW, I never knocked on doors that said no soliciting, I was not going to antagonize someone who had so clearly indicated they do not wish to be bothered, what is the point? If anything, you would just be turning them away from your message. The same with Beware of Dog signs, they are there for a reason, why risk a dog bite?
While the dog owner is primarily responsible for the attack, if that sign was in the window, obviously it meant there was an aggressive dog in the home, I think the ladies are at least partially to blame, they should have skipped that door.
Still a tragedy, I wouldn't wish that on anybody. I hope they recover fully.