Technical note / Defect ('illah): (2) In the manuscripts, "أولئك" is written in place of "كانت", which contradicts the script of the Mushaf and the recitation.

Grading: (3) Its chain is "talif" (ruined, i.e. severely weak). Ja'far bin al-Zubayr is "halik" (abandoned), as al-Dhahabi said in "al-Talkhis".
Technical note / Defect ('illah): Al-Qasim is Ibn 'Abd al-Rahman al-Dimashqi, and Abu Umamah is Sudayy bin 'Ajlan al-Bahili.

Reference / Source: Muhammad bin 'Uthman bin Abi Shaybah recorded it in "al-'Arsh" (12), al-Ruyani in his "Musnad" (1278), and Ibn Battah in "al-Ibanah al-Kubra" (7/ 175-176), via two routes from Isra'il, with this chain.

Reference / Source: Al-Tabarani (7966), Abu al-Fadl al-Zuhri in his "Hadith" (497), and Abu Nu'aym al-Asbahani in "Sifat al-Jannah" (438) recorded it via several routes from Ja'far bin al-Zubayr, with it.

Reference / Source: It has also been narrated from Abu Umamah as "mawquf" (a statement of the Companion), via Abu Fadalah al-Faraj bin Fadalah, from Luqman bin 'Amir, from him, who said: "Al-Firdaws is the navel (centre) of Paradise." Adam bin Abi Iyas recorded it in his "Tafsir" (1/ 451), Ibn Abi Shaybah in "al-Musannaf" (13/ 148), Hannad in "al-Zuhd" (49), and al-Tabari in his "Tafsir" (16/ 36).
Grading: This chain has "weakness" because of Faraj bin Fadalah, but it is in a much better state than the marfu' narration.

Note / Clarification: "سُرَّة الجنة" means: the noblest and finest part of Paradise. See "Taj al-'Arus" (root: s-r-r).

Important point: What makes this report unnecessary is the marfu' hadith of Abu Hurayrah (may Allah be pleased with him) in al-Bukhari (2790): "When you ask Allah, ask Him for al-Firdaws, for it is the middle of Paradise and the highest part of Paradise." It has already passed with the author (al-Hakim) at no. (270). "أوسط الجنة" means: its most balanced and most excellent part.