How sound is the hadith: "He who dies without knowing the Imam of his time dies a death of Jahiliyyah (ignorance)," and what is meant by the Imam in this hadith?

The aforementioned hadith, in its exact wording, has not been found. However, similar narrations have been reported, such as: "Whoever dies without having a pledge of allegiance (bay'ah) on his neck dies a death of Jahiliyyah (pre-Islamic ignorance)" (Narrated by Muslim), and "Whoever dies without having an Imam over him dies a death of Jahiliyyah" (Narrated by Abu Ya'la with a good chain of transmission). The intended meaning of "Imam" is the guardian of the affairs of the Muslims (Wali al-Amr) who looks after their religious and worldly interests, as stated in the hadith of Hudhayfah: "You should adhere to the main body of the Muslims (jama'at al-Muslimeen) and their Imam" (Narrated by Muslim).