Is the Hadith that speaks of a caller on the Day of Judgment, "Where is Al-Farooq?" and of honoring Umar ibn al-Khattab and forgiving his sins, authentic?

This narration was mentioned by Al-Muhibb Al-Tabari in "Al-Riyad An-Nadira", but it has not been found with a chain of transmission (musnad). Its absence from the well-known Islamic hadith collections is an indication of its weakness, as Al-Muhibb Al-Tabari may cite weak hadiths without drawing attention to their weakness.