In ISLAM the commandment of ALLAH is supreme and final!!!! when HE asked the brother of YUSUF(JOSEPH) MAY PEACE BE ON HIM,HIS brothers prostrated before HIM....so it all depends upon the commandment of ALLAH...if HE order us to bow before any human we the muslims will do it...if HE ask not to ANYONE except HIM..WE the muslims are obeying it.....