I'm sorry to hear that things didn't work out but your other cats need to be able to live in a stressfree environment. I can relate to what you're going through because I recently had to rehome my Cirrus. At least you're not waiting for 2 years like I did. Sometimes personalities just clash and theres nothing you can do about it.
I hope that Kahlua will be able to find a new loving forever home. Good luck.