Route A — down the shaft
Take the cathedral elevator down two floors. The key is in the room Nova’s line also uses. Go up one floor, through the door that key opens, and you come out under the elevator, which is where the node door sits. If the statue’s bar flashes red, you arrived correctly and your clock is short. That is not a missing key.
Route B — the balcony
Ride the elevator to the top floor and jump from the balcony toward the courtyard. This is the second approach in the same Steam thread. It does not replace the key if a door on the down route is what you actually need. Use it when the shaft itself is the block, not when you skipped the key room.
Show a stronger hint
A red flash at the statue is a time failure. End the loop, pick up more crystals, and return. Do not hunt a second statue.
Show the sourced solution
Down two floors for the key, up one through the locked door, under the elevator. Or top floor, balcony jump toward the courtyard. On 1.0.0.63 and later the statue price is the nerfed one. No exact minute value is published.