Please leave your questions open for all.
Your friend is a victim of wishful thinking.
--- none can bear witness as the one who truly understands this Book by way of reason.” --- in 13:43 indicates anyone with a good understanding of the Qur'an. Allah does not say that it was Hazrat Ali or so & so. This is an example of putting words in the 'mouth of the Qur'an'.
Hazrat Abdullah ibn Abbas never wrote a tafseer of the Qur'an. He explained a few verses as other Sahaba did.
Shi'a Imams attach great importance to his permission for the so-called Mut'ah (temporary marriage).
It is said that his copy of the Qur'an contained the 'Qir'at' "Marry women ILA AJAL-IM-MUSAMMA" (until an appointed time.)
Ayatullah Syed Hussain writes that Allah and Rasul had permitted Mut’ah (temporary marriage) with women. Bukhari and Muslim narrate this permission and so does Musnad-e-Ahmad bin Hanbal, and that Hazrat Umar opened the door for adultery and fornication by forbidding God's bounty (Mut’ah). It is not uncommon for prostitutes to use Mut’ah as an excuse for their activities. Is it really possible to distinguish between temporary marriage and fornication?
Now the fun way to attain ultimate piety: One who does Mut’ah (temporary marriage) once in his life becomes equal in degree to Hussain. Someone who does it twice equals Hasan, three times equals Ali and Mut’ah four times in life makes one equal to Prophet Muhammad. (Tafseer Minahj As-Sabiqain)
SHAN-E-NUZOOL from Preface to QXP:
The Second Dilemma: It occurred when the commentators of the Qur’an, centuries after its revelation, tried to connect every verse with a certain historical event, calling the process Shaan-e-Nuzool (Circumstances of a revelation.) Here the words and terms of the Qur’an were given tailor-made meanings to fit the supposed story, with total disregard to their original vibrant meanings, concepts and messages.
This deplorable practice only serves to bind the verses of the Timeless Qur’an to some supposed incidents and chain the Word of God in another set of shackles!
A very significant Islamic jurist, Imam Ahmad bin Hanbal (d. 241 AH) in those early times saw the chaos and raised a very strong voice against this awful practice, "Three kinds of books are absolutely unfounded, Maghaazi, Malaahem and Tafseer” - (The exalted Prophet's battles, his dreams, and expositions of the Qur’an done by ancient scholars). [Ref: Tazkarah-til-Maudhua’at by Ash-Shaikh Muhammad Tahir Al-Makki and Maudhu’aat-e-Kabeer by Mulla Ali Qari]
Worst of all, and inevitably so, this conjecture of Shaan-e-Nuzool was attributed to the exalted Prophet and his noble companions. This led people into believing that this was how they (the Prophet and his companions) used to understand the Qur’an! So, the foundation of an Islamic decline was laid down and mankind was robbed of the Supreme Gift of guidance bestowed upon them by the Creator!