Oh I am so sorry to hear he passed. He looked like the fight was out of him in those photos. Please, you must show them to the neighbor. She had things like that happen to her but, it sure didn't make her do anything to prevent it. I feel so badly for you and all you lost, just feel sick.
You have no control over a dog running loose - we have them here all the time. The people just stand there yelling "come back here, come back here." like the dog is actually going to stop on a dime and give up all his fun for them. Especially when the know they'll get the poo kicked out of them if they do return.