Did Al-Dhahabi, in "Tadhkirat al-Huffaz," use the statement of Umar ibn al-Khattab, "The Book of Allah is sufficient for us," to describe him as being among the Khawarij?

This text responds to the misconception that 'Umar ibn al-Khaṭṭāb, may Allah be pleased with him, refused to write down the Prophet's will by saying, "The Book of Allah is sufficient for us," by presenting the following points:

1. The narration is mursal (lacking a Companion in its chain) and weak, and therefore cannot be used as proof. 2. Al-Dhahabi's statement did not refer to 'Umar, but rather to the Khawarij who reject the Sunnah. Abu Bakr and 'Ali also made similar statements indicating verification, not a rejection of the Sunnah. 3. The Prophet, peace and blessings be upon him, agreed with 'Umar's statement, and writing the will was not obligatory for him. Allah protected him from anyone preventing him from conveying his message. 4. 'Umar's words are consistent with the verses of the Holy Quran which affirm that the Quran is a clarification for everything, such as: "Is it not sufficient for them that We revealed to you the Book which is recited to them?" and "And We have sent down to you the Book as clarification for all things," and "We have not neglected in the Register a thing." 5. If the Prophet, peace and blessings be upon him, had ceased writing out of compulsion, this would contradict his infallibility. If he ceased by choice, did he then choose the misguidance of the Ummah? 6. 'Umar and the Companions' abstention was motivated by compassion for the Prophet, peace and blessings be upon him, their understanding that the matter was a guidance, not an obligation, and their reliance on the Quran being sufficient and "a clarification for all things."