Hello! You should indeed be able to cut the thorns, but not with the blade alone; you need to craft a gadget using the blades and the handle/port, then interact with the thorns with the new gadget in hand. (You can close & reopen the inventory and it should save your current gadget. Also, you can hit disassemble at any point to return the components to your inventory.)
Admittedly our instructions didn't explain the crafting very well, but to make gadgets, you just have to drag the component items you want into the big dark section of the inventory and hit 'mix'. Let me know if this helps you progress.
Also, good luck with the video, we'd love to see it if you finish it!
