I'm very happy to hear that you've managed to rehome him and I hope that it works out well.
The problem is that occasionally you get a dog whose brain seems to be wired incorrectly. In December 2019 I had my fox terrier put to sleep after he bit me so badly that I needed stitches.
The first thing that he did was to attack us if he saw us carrying a kitchen roll. He also used to attack me when I was trying to cut my other dog's hair. We put it down to the fact that his tail had been badly docked, leaving a very tiny stump which he couldn't wag. He was one of 4 puppies that had been handed to a charity and we concluded that someone had done a bad dock of the docking and therefore couldn't sell them (Docking was then still allowed in France - not sure if it is now).
Over the 6 years that we had him whenever he fell asleep at my feet he would jump when I got up and attack me. I have several t-shirts and blouses with tears - he could jump a few feet of the ground. I discussed this with vet who recommended a behaviourist but they're not that common here and some of them only do work for court cases.
In France, if you have to have a dog put down you have to wait for 15 days (if they are well) so that checks can be made for rabies. So we lived with for 2 weeks and I was constantly thinking that I'd done the wrong thing.When the day came I said to the vet who told that it was the only thing to. I could not stay in the room and left my husband with him. Previously I'd always been with my other dogs.
I think about him often and am feeling very sad as I write this. After he'd gone, we realised how strange his behaviour had been, unlike any other dog that we've had.
We adopted another dog last January, aged 8 1/2 - he is like a goatskin rug - 50 shades of grey - and also blind. My other dog, Ruby, who is now diabetic is also blind in both eyes now but we manage OK. Both of them are soft and affectionate.
Callistemon Apart from one puppy that I bought (a Cairn terrier) all my dogs have been adopted - 2 puppies and 7 adults and apart from Django, the foxy, they have all been fine. There are plenty of dogs in the shelters whose history known.