I have a cat, Skittles (I call her Tubby). When she was a kitten, I left her and her brother Snickers in my apartment. There was a bowl of food and water in every room of the house. I left water in the tub in case they managed to tip over the water. What I didn't plan on was that the wind would blow one of the bedroom doors closed, with Tubby on the inside. I was gone 2 days, and by the time I'd gotten back, she'd tried to claw her way out from under the door and caused some bad chafing on her front paws in the process.
I'm not a bad pet owner, and sometimes things happen. Dede sounds like she left the puppy in a room, not a crate, and tried to figure out what the puppy was doing to hurt itself, and figured out after a few days that he was sticking his nose under the rough door. She didn't force the puppy's nose under the door and take the chunk off the puppy's nose herself. She couldn't figure it out for a few days.
I don't agree with taking the food and water from the puppy, but then I also don't know how long she was gone during the day. Was it for an hour, a couple hours, what? I don't know.
All I know is this was blogged 2 years ago about something in her indeterminate past, and I can't see how it pertains to Kyron, since Kaine says she was rarely at his home, and can't remember more than a few times he's ever seen her.