Once again, it's an easy solo. You might want to get Book shell from outside before you do it. I have literally never seen a Fire Break resist, and if you sacrifice DD Atma for fire resist Atma then you'll end up with a longer fight that has more Fire Breaks and a higher chance of getting one-shotted.
Again, I think you're getting worried about the wrong things. The hardest part of the Itz path is Tunga.