At the end of my rope with my dogs fighting

I'm not sure what to do anymore. I have read all the guides, I have engaged two different trainers, I have them walked twice daily, and I have been to the vet to rule out health issues. I have two dogs: Ludo (husky/mix, age 5) and Daisy (pit mix, age 2). We have had Ludo for a few years, Daisy we adopted 3 months ago.

About 3 weeks into owning Daisy, she and Ludo got into a fight over a toy. It wasn't terrible, we separated them and I called a trainer immediately. We had the trainer come into the house, they gave me sibling jealousy protocol, and I've been working through that with them. I also separately took them to obedience training with a different trainer. I took away all the toys in the shared area and made it so they could only play with toys in their own rooms away from one another.

Then one day we were sitting on the sofa and they were between my legs and a fight broke out. Daisy latched onto Ludo. My husband was hurt in the process of tearing them apart. I tried the wheelburrow method but could not get them apart. Ludo was injured but not terribly. I called the trainer back, we continued with the sibling jealousy protocol (keeping them on leashes while they were together). Things were fine for several weeks.

Then two nights ago, my son was cooking hot dogs and spilled some water on the floor. The dogs went to lick up the water and Daisy went after Ludo. His leg was torn up in the process.

I'm not sure how to stop this. I'm on edge 24/7. 99% of the time they are completely fine with one another. I do not want to rehome either dog. Is there anything I can do to end this drama and find peace?