Why is the Ibadi school of thought attributed to Abdullah ibn Ibad instead of Jabir ibn Zayd, whom the Ibadis consider their founder? And is there an e-book that discusses them in detail?

Abdullah ibn Ibad Al-Tamimi is the head of the Ibadiyya and one of the leaders of the Khawarij in the second half of the first century Hijri. The information available about him is scarce and inconsistent, but he lived during the time of Muawiyah and Abd al-Malik ibn Marwan. He joined the Khawarij in supporting Ibn al-Zubayr against the army of Al-Sham, then he separated from him after Ibn al-Zubayr praised Uthman (may Allah be pleased with him). After separating from Ibn al-Zubayr, he differed with the Khawarij regarding the ruling on those who disagree with them. He said: "The people are disbelievers in blessings, and they are not polytheists." The Ibadi doctrine settled on the belief that disobedient Muslims and those who oppose them will abide eternally in Hellfire, but in this world, they are disbelievers in blessings and not polytheists. It is permissible to live with them, deal with them, and fight them without enslaving their women or seizing their wealth, except for horses and weapons. It is said that he recanted his Kharijite doctrine at the end of his life, but his followers continued to attribute themselves to him.