Is queenside castling allowed in this position from chess960?

Assume that we have this 960 position and these few opening moves:

Now white to move, is queenside castling legal?

Taking the explanation from here:

https://www.chess.com/article/view/how-to-castle-in-fischer-random-chess

- No King or Rook has moved,
- King is not in check on any of the involved squares,
- No piece is currently standing between the King and the Rook

Yes! There is a Bishop standing between the King's current square (g1) and target square (c1).
But the explanation, to which I gave the link, does not mention that this would make castling illegal.

So this is the whole point of my question, is queenside castling allowed in this position, despite the presence of a Bishop on e1?

I found the FIDE guidelines for castling in chess 960:

https://rcc.fide.com/guidelinesii/

There it is stated:

"All the squares between the king’s initial and final squares (including the final square) and all the squares between the rook’s initial and final squares (including the final square) must be vacant except for the king and castling rook." (II.3.2.7.4)

(That settles the matter in the position given in the OP here.)

One might wonder if positions exist that comply to II.3.2.7.4 but still have another piece between the King's initial square and the Rook's initial square. I believe that that is logically not possible.