This implies that Humaid was in the army of Shamir bin Dhi al-Jaushan al-Kilabi...
This implies that Humaid was in the army of Shamir bin Dhi al-Jaushan al-Kilabi, especially after taking into consideration his constant conversation with Shamir, censuring him in a number of matters; and [secondly] his presence in the tents after the martyrdom of al-Husayn (as), knowing that it was Shamir who attacked the tents with the foot soldiers. Later, we see [Humaid] participating in the uprising of the Tawwabun (5:555).
He used to visit Mukhtar in prison, but [at the same time] he cautioned Sulaiman bin Surad al-Khuza’i against him, informing him that Mukhtar was inciting people to betray him. [However,] Sulaiman ignored this action of [Mukhtar] (5:581&584). [Humaid] later returned with the defeated army of the Tawwabun (5:606). He was a friend of Ibrahim bin al-Ashtar al-Nakha’i whom he used to frequently visit and go with him to [see] Mukhtar every evening–after the Tawwabun uprising.
They would plan their affairs till late night and then disperse (6:18). One Monday evening Humaid came out with Ibrahim from his house with a group of about a hundred [men]. They were armed with swords and were concealing their shields under their cloak-like garments (6:19). They advanced till they came to the house of Mukhtar on the night he departed.
(6:23) However, when [Humaid] came to know that Mukhtar is determined to kill the assasins of al-Husayn (as), he rose together with ‘Abd al-Rahman bin Mikhnaf al-Azdi, Abu Mikhnaf’s uncle, against Mukhtar. When ‘Abd al-Rahman was wounded, Humaid recited some verses in sympathy for him (6:51). When ‘Abd al-Rahman bin Mikhnaf escaped from Kufah and sought refuge with Mus’ab bin al-Zubair in Basrah, Humaid also joined him there (6:58)!
His name last appears in al-Tabari (6:213) when he recited couplets in lamentation of ‘Abd al-Rahman bin Mikhnaf who was killed by the [followers of the] Azariqah [sect from the] Khawarij near Kazarun in 75 H, as he was fighting them along with Muhallab bin Safrah on behalf of Hajjaj bin Yusuf al-Thaqafi. Al-Dhahabi has mentioned [Humaid] in Mizan al-I’tidal (