I did try mixing some of her usual food with the kd. The first time she ate a few bites but after that na da.
I put her back on her usual food yesterday because she was getting a bit wobbly when she walked. She ate fine since then. So, it seems I'm faced with : do I try to make her eat it by forcing her to eat something she hates and maybe extending her life a little longer, or do I just let her eat what she likes and enjoy what she can of her life, that might be shorter because of it?

The vet said don't let her have anything else and she would eat after 2 or 3 days. I don't call that being helpful. I call it being cruel. The poor cat is already blind and getting a thyroid pill poked down her every day. She doesn't do any thing but eat, sleep, and potty now. Do I want to take the enjoying eating away from her? I'm leaning toward no at the moment.