The locale may have changed, but Kushala Daora’s attacks have not, nor have the solutions to dealing with them (read: lots and lots of Flash Pods). The fight will most likely start in AREA 5, after which Kushala Daora will most likely move to AREA 4, then AREA 1. When wounded, it’ll flee to the nest in the boughs of the Ancient Forest, in AREA 16, which seems to be where ever critter with wings sans the Pukei-Pukei prefers to roost.

When you complete this quest, return to the Armory clerk and she’ll give you the hunter tool she was working on - an Apothecary Mantle, which will increase the efficacy of weapons with ailment attacks while worn.