I think you are making the right choice. There are cats who need and want to be an only cat. In the past we had a male Aby who did not tolerate other cats or dogs and he had a terrible temper about the whole thing! There were even people he didn't like and he would just walk up and bite them but he was as sweet as can be to us.

Ti sounds like he wants to eliminate the other cats around him so he can be the only cat. Also, Bengals are terribly close in breed generations to wild cats and may not be as domesticated as you need for your well domesticated Abys. As much pain as he's brought, I know you still care for him and your own efforts to rehome him will give you greater comfort in knowing he will be well cared for. He will probably be happier where the stress is lower and he runs the place. Cats can and do share your pain and I know he is aware that there's something wrong but not that he is the source of the pain.

Follow your heart.