Dogs can be easy. They want to trust, they will return to an abusive owner again and again, simply because that's the way they are. It's built in, that they need to be part of a pack, and if the head of that pack walks on two legs, well, it still counts. Even if he thrashes them soundly, it's part of the strict discipline of the wolf pack, and something their doggy brains comprehend. They keep coming back.
With cats, you don't command trust, you just hope for it; and when one honors you with a purr or allows you to pat them, no matter how gingerly, you feel as if you've been gifted. These two cats have been damaged. Hit, struck, things thrown at them, I don't know. When you reach out to them they wince, they cringe. I've seen it before, and it breaks my heart. So we tread lightly, talk to them, let them have all the time they need.
It could take all summer, it could take longer. No matter. It will happen, on their terms, not mine. And that's cool too.