After having suffered that fight as a dragoon whose hotbar was still a mess. An FC friend did the same fight effortlessly as a Machinist. And yes I was very salty XD
Realistically though , a gun is probably the worst thing to bring to a fight , even a WHM would do more damage since its magical and not a metal pellet.
I did this fight as a drk. So all I heard in my head after I summoned fray was “FIGHT BACK! FIGHT BACK!” We jumped zenos like 10 times in that fight and he literally couldn’t kill me even if he wanted to tbn plus multiple revives is a seriously broken combo lol. Still wish there was a way to actually replay the fight outside of new game plus tho