I heard the Messenger of Allah ﷺ say, "Whoever among you is able to die in Madinah, let him do so, for I will intercede on the Day of Resurrection for whoever dies there, and I will bear witness for him."
سمعت رسول الله ﷺ يقول: من استطاع منكم أن يموت بالمدينة فليمت، فإنه من يموت بها أشفع له يوم القيامة، وأشهد له.
Nasai narrated it in Kubra, and Ibn Abu Asim in Al-Ahad wal-Mathani (9382), via Aqeel, from Zuhri, from Ubaydullah (bin Abdullah bin Umar), from Abdullah bin Utba, from Sumayta, and he mentioned it. Its chain of transmission is sahih.But Yunus narrated it from Zuhri, from Ubaydullah bin Abdullah bin Umar, from Sumayta, omitting Abdullah bin Utba. Tabarani narrated it by this route in Al-Kabir (24/331). Ibn Hibban narrated it in his Sahih (3742), saying, from Ubaydullah bin Abdullah bin Utba, from Sumayta. It appears an error occurred in the chain of transmission.Al-Hafiz mentioned in Al-Isaba (4/351) the narration of Yunus, from Zuhri, from Ubaydullah, from Sumayta, a woman from Banu Layth, reporting that she heard (and he mentioned it). He added that Zuhri said, "Then I met Abdullah bin Abdullah bin Umar and asked him about her hadith, and he narrated it to me from Sumayta." This is the narration of Ibn Wahb from Yunus, and it agrees with the narration of Aqeel.Utba narrated it from Yunus, and he inserted Safiya bint Abu Ubayd between Ubaydullah and Sumayta. Ibn Abu Dhib narrated it from Zuhri, saying, from Ubaydullah, from an orphan woman, from Safiya bint Abu Ubayd, from the Prophet ﷺ. End of quote.I say, the orphan woman is Sumayya, in the diminutive form, al-Laythiyya, also said to be al-Dariyya, and she was an orphan under the care of Ayesha. So the hadith revolves between being part of the musnad of Sumayta or that of Safiya bint Abu Ubayd. The latter is the wife of Abdullah bin Umar, and it is most likely that she did not narrate from the Prophet ﷺ, but rather narrated from his wives such as Ayesha, Hafsa, and others.