ʿAbd al-Hādī; for that reason I am of the opinion that the statement was inadvertently reversed in some copies. Allah knows best.
This report, though, is mawqūf, and its isnād is sound: all its transmitters are trustworthy and are narrators cited by the two Ṣaḥīḥs, apart from Ibn Abī al-Wazīr—Muḥammad ibn ʿUmar ibn Maṭraf, Abū al-Maṭraf al-Basrī—who is himself reliable, as al-Taqrīb affirms.
A marfūʿ version also exists. Al-Ṭabarānī recorded it in both al-Kabīr and al-Awsaṭ with the wording: “lā tushaddu al-riḥāl” (“saddles are not fastened”). Al-Haythamī remarks (4/4): “Its narrators are all trustworthy.”
I later located a full marfūʿ chain. Al-Azraqī, in Akhbār Makkah (p. 304), states:
“My grandfather related to me, saying: Sufyān narrated to us from ʿAmr ibn Dīnār, from Ṭalq ibn Ḥabīb, from Qazʿah, who said: I intended to travel to Mount Ṭūr, so I asked Ibn ʿUmar. Ibn ʿUmar replied, ‘Do you not know that the Prophet ﷺ said, “Saddles are not fastened except for three mosques: the Sacred Mosque, the Prophet’s Mosque, and al-Aqṣā Mosque. Leave Mount Ṭūr aside and do not go there”?’”
This chain is sound; its transmitters are the reliable narrators of the Ṣaḥīḥ. Al-Azraqī’s grandfather is Aḥmad ibn Muḥammad ibn al-Walīd al-Ghassānī, a trustworthy narrator included by al-Bukhārī.
Sixth chain: ʿAlī ibn Abī Ṭālib.
Al-Ṭabarānī recorded it in al-Ṣaghīr (p. 98) and likewise in al-Awsaṭ through the route of Ibrāhīm ibn Ismāʿīl ibn Yaḥyā ibn Salamah ibn Kuhayl al-Ḥaḍramī al-Kūfī, from his father.