Quick note: Once defeating Craftwork, you can access the upper room with the Crusaders armor and Familiar: Silver Knight by manipulating the pillar to the right side and jumping up normally. You do not need double jump.

Why is there no map for this?

The revisited page - you can't jump up to the bell tower with normal double jump nor the normal ray, only after upgrading it with bovine feather. So the timing of the bell tower is wrong in the walkthrough.