Assalamu alaikum,
Don't get tricked by this youtube channel. It is meant to be sarcastic. In his channel's about section it says" Islam is the one true religion- my imam says so, so it gotta be true". He is basically trying to lure Muslims into entering his videos, it's a trap.
Most of the claims against the textual integrity and the preservation of the Qur'an has been refuted over here:
http://www.islamic-awareness.org/Quran/