That totally makes sense to me. But it seems like the only solution for the time being.
Chester was a rescue dog and my girlfriend is the 3rd or 4th owner. She got him when he was 3 I think. He is 7 now and although my girlfriend has trained him and taken him to obedience school, he doesn't always listen. I've seen him playing with other dogs and he is very submissive and mellow. But sometimes he approaches other dogs very quickly which seems threatening. I feel he's very gentle with people and dogs, but instinctively wants to chase small fast critters like squirrels and would probably kill them if he could catch one. My girlfriend disagrees and thinks that he would never even hurt a squirrel. I totally disagree. This is very frustrating for me!
So, the main issue with your advice, and the cause of my stress is that my girlfriend thinks Chester won't hurt Rajah. And, I disagree. So, we've brought Chester without a leash into our room (Rajah's safe room) every day since we've got him. Rajah plays on our bed which is raised up to about to Chester's eye level. Chester watches intently as we keep a close eye. We tell him "sit" and "stay" which he knows but doesn't alway obey. Chester has lunged up on the bed, where he knows he is not allowed, and chomped at the cat. We've both witnessed this 3 times, but somehow my girlfriend STILL doesn't think that Chester would hurt the kitten.
My girlfriend tried to let Chester sleep on her side of the bed on the floor while Rajah slept on my bedside table. Chester would get up and sneak over to my side and stalk the kitten. We ended up putting Chester in his crate in the living room because he wouldn't "stay" when we told him. He usually whynes if he is locked out of the bedroom with the door closed when we're in there.
I think the cat's frisky and quick moving play is a trigger for Chester to chase, just like squirrels. This trigger will turn off any ability of his to listen to commands in my experience. He has trouble obeying commands as is.
The other thing that is driving us both crazy is that Rajah's safe room is also our room. He wakes us up in the morning around 3:30 by scratching and biting us. He also does this when we go to bed at night and I end up staying up until 11 or midnight playing with him until he will go to sleep. So, I haven't been getting enough sleep. Alternatively Rajah started meowing when my girlfriend got up to go to the bathroom at about 5:30. So, I took him out and played with him for a while then put him back in the room where I plan to keep him during the day.
I just don't know if this will ever work out