WalaikimasSalam!
I had read entire Biyan ul Quran. It is correct that he said that many scholars consider this Surah Madani. But he himself prefer it to be Makki because of its structure, content, size and rhythm. Moreover many other famous scholars like Amin Ahsan Islahi also consider it a Makki surah.
In my opinion it is not Madni suah as well but the point which I want to address is that there is no concession about this claim and you should not addressed it in this book if you claim that it is approved by entire sects in ummat