The hadith master Abū al-Qāsim Ibn ʿAsākir (1) said: that is to say, they heard the report, and his death took place in Byzantine territory.

Ismāʿīl ibn ʿAyyāsh narrated—through Shuraḥbīl ibn Muslim—from Saʿīd ibn Hāniʾ, who said:
Muʿāwiyah declared, “The calamity—every calamity—is the death of Abū Muslim al-Khawlānī and Kurayb ibn Sayf al-Anṣārī.”
Its chain of transmission is acceptable.

On this basis Abū Muslim would have died before Muʿāwiyah, unless the Muʿāwiyah meant here is Muʿāwiyah ibn Yazīd (2).

Al-Mufaḍḍal ibn Ghassān al-Ghallābī said: “ʿAlqamah and Abū Muslim both died in the year 62 AH (3)—and Allah knows best.”

In Darayya there is a visited grave that is said to be that of Abū Muslim al-Khawlānī, and that is plausible.

3 – The Reciter ʿAbd al-Raḥmān ibn ʿAbd al-Madanī * (ʿ)

It is said that he was a Companion, although he was only born during the lifetime of the Prophet.

Abū Dāwūd said: “He was brought to the Prophet ﷺ while he was still a young child.”

Al-Zubayr ibn Bakkār said: “ʿAḍal and al-Qārrāh are the two sons of Yathīʿ (4) ibn al-Hawn ibn Khuzaymah ibn Mudrikah.”