My Cat Hates My Puppy – Help!

Hi y'all, I'm hoping for some judgement-free helpful advice as I'm feeling kind of like I don't know what to do anymore.

I adopted my miniature poodle puppy about 4ish months ago. She is a sweet and loving girl and definitely my soul dog. I also have two cats that I have had for a few years now. We kept them completely separate for the first week or so after getting my puppy and only did scent exchanges. Then, greetings through the door, then meetings where I'd carry the puppy into the room where the cats are and letting them sniff her while I gave everyone treats. I'd do this for a while– go into the room, let the cats see the dog while she's in my arms and pet them etc. But one of my cats, Sissy, absolutely hates her.

From what I can tell, she doesn't necessarily act afraid of the puppy, as she watches her around the room like a hawk and like she wants to pounce on her. She will eat meals and treats if the puppy is in our arms in the same room, and even accepts pets from us lovingly and rolls around on her back to show her belly too. Sometimes, the puppy will accidentally get into the bedroom (where the cats are) and Sissy will immediately chase after her and try to attack her. She attacks her through the crack in the door, and even drew blood once. A few times when I had to do work in the bedroom (which is absolutely so difficult with the current beef between my cat/puppy,) so I put the puppy in her crate on my bed and let the cats roam around. Sissy goes up to the puppy's crate and hisses very violently, makes that scary cat meow noise, and has even tried to swat her. My other cat loves the puppy and they get along just fine.

I genuinely don't know what to do anymore. I feel like we've done everything recommended to us by the internet and from a conversation we had with behaviorists at our local shelter. I'm really scared that Sissy will seriously hurt the puppy as she is so much bigger than her and tries to hurt her every chance she can get. The puppy is so gentle too while I think Sissy on the other hand would show no mercy if they did get into an ugly fight. It's also difficult because we are still sleeping in our living room because the puppy freaks out if we aren't there with her (yes, she sleeps in her crate.) I just want peace in my home again and to be able to live in it normally.

TL;DR – My cat really hates my puppy and I feel like I have seriously tried everything, including slow introductions, talking to behaviorists, etc. Looking for perhaps some creative advice or what has worked for anyone else.