This sounds like a fight that erupted over a desireable object.
It may be you have been elevating the status of the wrong dog and its the younger dog who is naturally the more dominant. You've been trying to put her in second position to you as well as to the other dog. You humans she will agree to being the leaders, but she may then feel she can be second to you, and that your other dog must be third.
This is a great breed but they are designed through generations of breeding to arouse or excite quickly and act decisively when aroused. A small tussle can easily blow up into a big fight very rapidly.
If something as low value as a stick can trigger this then they could get into real trouble over a real food type chew treat, or your attention, which are more highly valued items.
While I do not think this makes either dog 'bad' I do think it may mean these two cannot live together, particularly as it sounds like they are the same sex which increases the potential for dominance issues.
You may be able to work this through with a trainer's help, though it may take relegating your original dog to second place dog rather than first.
It can make life stressful while you are trying to work this out.
I'd suggest seeing if your vet or a local shelter can refer you to a really good trainer or a veterinary behaviorist to evaluate the situation and see how much it will take to allow them to live together with you peaceably.
It may not be possible for you or them to do so and recognizing that soon and finding one a single dog home might be the best choice.
I know how hard this is but even we humans sometimes can't live together, so too not all dogs can manage to do that.
Hope this helps you!
Dog Expert:Rescue, Train,Breed,Care
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics
You are welcome - she may be a great dog if there isn't any competition for who's #1.
Thanks for your accept!