There is a pickup under where you start the Kwolok fight which is commonly known as the Kwolok revisit pickup because you normally need to fight Kwolok before getting it. You can actually get that pickup before doing the fight by avoiding the trigger which starts the boss fight.
Be carefull when collecting the pickup: if you go too far on the left you will be softlocked and you'll need to reload your savefile. If you only collect the pickup and go back to the right, you shouldn't have any problem.
Going above the trigger
With enough height, you can go above the trigger of the fight, letting you get that pickup without fighting Kwolok. You want to climb the left wall and then drop once you reach the right wall.
Breaking Kwolok's wall
There is a wall between Kwolok's fight and the keystone room. By using Shuriken break, you can break that wall from the wrong side, letting you get that pickup without water dash or fighting Kwolok.
The problem with this Shuriken Break is that you need to stay in the spikes. While the position isn't hard to get, you will quickly lose a lot of health. Remember that you can jump back in the water and found a spot to Regenerate your life before coming back to the spot if needed.