Level 3 is like what you've said. The spikes position at the top is the same as spikes with no collision at the bottom, but the spikes at the top shown on different layer every time you die (the collision layer never change, just the visual layer). So, you need to know where the spikes position at the top on both layers in order to pass through ^^
This is the level 3 -> [Spoiler] Level 3 Hitboxes