When is Gamma Draconis closest to the zenith in London on April 4th
I read this as "Benenaim" (another name for Alkaid) too (not Etamin, which is another name for Gamma Draconis), and that star does indeed transit the meridian near midnight on April 4th (12:44am to be more precise). Note that the hour angle is 0 in the Stellarium screenshot below, and the star is only 35 minutes from the zenith position: