Gets a little hairy toward the end but I beat him 3 times with the rustshard hammer, I forget the name but it was obviously the tier before you get elder dragonblood.
I recommend getting the master cola + veggie buff that gives felyne moxie and bombardier. And speed gather, and using 20 ballista shots in the chest.
It seems like chacha and kayamba help out a bit in the fight, they even get an ability that boosts their cannon/ballista damage. But it's mostly on you.
I failed it my first try which was kinda disheartening but then I remembered some of the tricks, like gonging him when he tries the bellyflop.
