The hadith has two supporting narrations:

One is the narration of Ali, transmitted by Muhammad ibn Abd al-Rahman ibn Abi Layla, from al-Hakam and al-Minhal, from Abd al-Rahman ibn Abi Layla, from his father, from him.

It was recorded by al-Nasa’i (5/108–109), al-Hakim (3/37), al-Bayhaqi (5/212–213), and Ibn Abi Shaybah (18729). The latter joined Isa to al-Hakam and al-Minhal; in al-Hakim’s version, Isa appears in place of al-Minhal. He said:

“The chain of transmission is authentic!”

Al-Dhahabi agreed with him.

Muhammad ibn Abd al-Rahman ibn Abi Layla was well known for his poor retention. Thus, he is suitable for supporting evidence. In the versions other than al-Hakim’s, there is mention of the two ʿUmars—Abu Bakr and Umar—but not of the accusations of cowardice.

It also has another route from Ali, transmitted by Nuʿaym ibn Hakim, from Abu Maryam al-Hanafi, from Ali.

Al-Bazzar recorded it (1815) at length, including mention of Umar and his companions being defeated; al-Hakim also recorded it, though he did not cite it in full. However, he mentioned the defeat and added the accusations of cowardice. He—and al-Dhahabi—said:

“The chain of transmission is authentic.”

I say: The status of this Abu Maryam al-Hanafi has not become clear to me, for they differed over his tribal affiliation: was he al-Hanafi or al-Thaqafi? They also differed over his name: was it Qays or Iyas? Ibn Hibban and others declared Qays trustworthy, whereas no one besides him declared Iyas trustworthy. Thus, if he is trustworthy, the chain is authentic; otherwise, it is authentic in light of the routes and supporting narrations mentioned above.

The other supporting narration is from Salamah ibn Amr ibn al-Akwaʿ, transmitted by Muhammad ibn Ishaq in al-Sirah (3/385–386, Ibn Hisham); and through his route by al-Hakim (3/37),