It looks like I'm not the only one having this issue, but in the rising lava level it is impossible to progress as intended because the pass through platforms at the second solid platform are just a pixel or two too high, making it impossible for the characters without two jumps to progress. I only managed to get past it by getting Gratia up to the level, then having Elle get up to the box by using a wall jump, which only Elle and Gratia can do, then pushing the box all the way back down to the platforms on the right, which was it's own glitchy work around, so that ? could climb up.