Qirat Al Ammah
Every discussion on this topic has to be seen under the fact that the Qirat Ammah has been the common reading; if a scholar finds something contrary to it, his findings or perception is wrong because the fact remains that Quraish passed on this Quran to others. If Hamzar is there in the Quran, Quraish pronounced it. Otherwise, it would be a massive problem and should be reported in the history accordingly.