If you examine the statement carefully, it’s talking about faculties necessary for validity.
That is not the same as faculties necessary to do it at all. The statement is saying that bishops can validly confirm. However, if he does not have the permission of the Ordinary of the Diocese, such confirmation is illegal.
Yes, the diocesan bishop can tell his auxiliary that he cannot confirm and the auxiliary is bound to obey and not to confirm, because he does not have the faculties or the license to exercise his episcopal ministry in this diocese.
Let’s take it to another sacrament. I was the superior for my community. I’m not a priest. I’m a religious brother. We have brothers who are priests. No bishop has faculties to ordain any of our brothers without a letter from the superior. The law says that an ordination by a bishop is valid. He does not need faculties for validity. But he he needs faculties for liceity. The only person who can grant him permission to ordain a member of a religious order is the religious superior. Even the local diocesan bishop does not have that authority. He can only grant the bishop permission to ordain within his geographical territory, not permission to ordain a Franciscan, Dominican, Jesuit, etc.
Everyone needs faculties to legally exercise his ministry, even if he has the faculties that come with the office. That’s one thing, another is the faculties that come with jurisdiction. In my example, the bishop who ordains one of my brothers without my permission does not have the faculties to do so, because he has no jurisdiction over my brothers. Only I, as the major superior have jurisdiction over them, not even the local diocesan Ordinary has jurisdiction over them. In that case, if the bishop proceeded to ordain without the faculties to do so, he would incur an automatic suspension. If the bishop is already suspended, he only aggravates the situation for himself and maybe for the recipient of the sacrament. In the case of an ordination, the newly ordained religious is automatically suspended along with the ordaining bishop and he incurs other penalties for violating obedience.
Faculties for validity are granted by the Church with the office. Validity is not enough. You need jurisdiction to exercise that ministry. That jurisdiction can only be granted by someone who has the canonical authority to do so. This is why Father says that the big picture gets very complicated if we do not look at the necessary faculties from the proper authority.
Fraternally,
Br. JR, OSF