Since it is not permissible to vocalize the intention, how is the loud recitation of the talbiyah in Hajj reconciled with the hadith of Anas?

The Shaykh : A new question: Since it is not permissible to vocalize the intention, how do they shout it, as in the following hadith: Anas (may Allah be pleased with him) said, "I was riding behind Abu Talhah, and they were all shouting it together: Hajj and 'Umrah" - narrated by al-Bukhari - ?
If the hadith is narrated in this form, it is an abridgment. If the writer of the hadith first transmitted it as he found it, and secondly understood that they were saying in the talbiyah: "Labbaik Allahumma bi-hajj" or "Labbaik Allahumma bi-'umrah," then the question does not arise; because this is the talbiyah.