Sanctuary for aggressive dogs?

My family has a cane corso who we adopted from a woman who lied about his breed, his age, and likely many other things. He had been aggressive since he was a puppy and has as a result been through extensive training, but despite him generally being incredibly well trained, he still flips a switch and becomes uncontrollably aggressive when he is guarding something. He could be guarding food, a toy, a human, there has been no good way to predict when he will become aggressive. He has been violent to children and small animals that we are frankly incredibly lucky he hasn’t seriously injured or killed anyone. He cannot be rehomed because he is genuinely dangerous, and he is as of the last incident going to be put down. I love this dog and am desperately trying to think of some way for him to have a good life without harming anyone. Does anyone know of a rescue or sanctuary that takes in aggressive dogs? Any place he would be safe and the people taking care of him would also be safe?