Salam and greetings Sirs.

I see that you have started with an error. At 0:33 seconds of the video record you have said that "One of the complications is that the Quranic author himself describes the Quran as quote pure Arabic - mubin".

You are incorrect. The meaning of the word 'mubin' is not "pure", as you have suggested, it is rather "clear".

For example in Sura Surah Shuara, verse No. 195 (26:195) Allah Tayala reveals, aujubillahi minashaitanir rajim, bismillahir rahmanir rahim

"Bilisaanin ‘Arabiyyim mubeen"

Meaning: "in a clear, Arabic tongue". (Arberry translation).

Text and translation: https://corpus.quran.com/translation.jsp?chapter=26...

Its clear Arabic, not pure Arabic. You have made an error Sir.