Hi,

Sorry for the delayed response. As I'm not a designer I can't for certain say this is the correct way, but how I've solved it is by doing the following:
* Drop down to hang on the pole (around where the flower shoots at)
* WIth Pontius, aim the the shield towards the purple orb so that the projectile will get deflected towards it
* Once the projectile is deflected, switch to Amadeus and quickly levitate the wall on the right up, so that the projectile can hit the orb. Note: while the projectile flies relatively slowly you still need to be quite quick, I've managed this with both KBM and controller so there should be enough time once you get the hang of it

Hope this helps, obviously one way (possibly the one you found) would be to attach a plank to the spikes underneath, going to the end of it (could even hang from a rope from the planks end to get even more room) and shoot the orb with an arrow. Whilst this might not be the first intended way, I feel like many puzzles encourage creativity and part of the fun comes from finding your own ways to solve the puzzles, even if they differ from the supposedly intended route.

Hope this helps.

- Teemu / Frozenbyte