I am so sorry that your little Zada has CT. As awful as it sounds, I think if you can get some weight off of her and keep her relaxed and in a cool environment you might be able to slow the progression down. Don't keep thinking that you are going to lose her....try to remain positive. She might surprise you.
I have had CT pups and have tried different treatments. I have found that they can respond differently. The specialist I went to with my last one had me alternating meds which seemed to work best for him. There are many different treatments. If that elixer does not work, that does not mean that other meds will not!! Please keep that in mind. I will be happy to share the different treatments we have used on my pups .. just PM me if you ever want to know. I am quite certain that the specialist you went to is aware of other treatments and will try them if this elixer does not work. That med has ephedrine in it...so I would definitely keep an eye on her heart rate as they said.
Keep us posted on her progress! I will keep her and you in my thoughts and prayers.