“Truthful.”
(See my comments on this biographical entry in my new book, Taysir Intifaʿ al-Khillan bi-Kitab Thiqat Ibn Hibban.) It appears that this Majalid is the man mentioned in Ibn ʿUyaynah’s narration from Abu al-Zinad, who said: “I heard a man relating to Kharijah ibn Zayd ibn Thabit, who said: ‘I heard your father, in this place at Mina, say...’” He then mentioned a similar report.
It also appears that, after Abu al-Zinad heard the hadith from the man, he heard it directly from Kharijah, as indicated by al-Tabarani’s first narration. The hadith has a supporting report from Ibn ʿAbbas. Ibn Jarir recorded it (5/138–139) through two routes from him, each strengthening the other; thus, through them, the hadith rises to the rank of authentic.
It is further supported by the hadith of al-Qasim ibn Abi Bazzah, from Saʿid ibn Jubayr, who said: I said to Ibn ʿAbbas, “Is there repentance for one who deliberately kills a believer?” He said, “No.” I recited to him the verse in Surah al-Furqan, and he said: “This is a Makkan verse, abrogated by a Madinan verse: ‘And whoever deliberately kills a believer—his recompense is Hell.’” Al-Bukhari (4764) and al-Nasa’i (4001) recorded it, the latter’s wording being cited here.
(Two observations:) First: all these preceding narrations explicitly state that the verse in Surah al-Nisa’ was revealed after the verse in Surah al-Furqan, except for the narration of Majalid ibn ʿAwf recorded by al-Nasa’i, whose wording is: