Why don't Muslims know any of these things that we have written and researched? Simply because "...Muslim leaders are afraid of carrying out any thorough research into the origins of Islam, especially, the pre-Islamic Arabian religion, in case they discover anything that will cause their faith in Islam to wane" (Who is This Allah, p.136, Moshsay, emphasis mine).
They also follow what Muhammad commanded them to do, and that is to: "O ye who Believe ASK NOT QUESTIONS about things which if made plain to you, MAY CAUSE YOU TROUBLE...Some people before you did ask questions, and on that account LOST THEIR FAITH" (Sura 5:101-102). He also says: "This book is not to be doubted" (Dawood, Transl Sura 2:1). Why not? Why not put it to the test? God in the Bible actually challenges us to prove the Bible. God is confident that the Bible is true. "PROVE ALL THINGS" (1 Thess 5:21).
Maududi in his commentary warns Muslims not to probe deeply into Islam: "The Holy prophet himself FORBADE PEOPLE to ask questions...so do not try to probe into such things" (The Meaning of the Koran, vol.3, pp.76-77, emphasis mine).
Bukhari's Hadith tells us how Muhammad responded to those who asked questions: "The prophet was asked about things which he did not like, and when the questioner insisted, the prophet got angry" (vol.1, no.92). Muhammad just wanted people to believe on blind faith. "Take my word for it!" Muhammad implies.