When the fight begins, target, then run forwards. Jumpslash right when the dinofols starts moving (shortly after Tatl moves to it), cancel the animation, then run forwards and jumpslash again before the dinofols breathes fire.
Kill the dinofols with one pound, then roll to where the chest will spawn. If the dinofols jumps (RNG), either try to pound it again or get a guaranteed kill with two punches.