If you use variants, you also need to replace the line:
echo $this->image->display($image->file_path,true,$image->file_name,'id="hikashop_main_image_'.$variant_name.'" style="margin-top:10px;margin-bottom:10px;display:inline-block;vertical-align:middle"','id="hikashop_main_image_'.$variant_name.'_link"');
by the line:
echo '<img src="'.$this->image->uploadFolder_url.$image->file_path.'" alt="'.$image->file_name.'" id="hikashop_main_image_'.$variant_name.'" style="margin-top:10px;margin-bottom:10px;display:inline-block;vertical-align:middle" />';
in the file show of the view product that you already edited via the menu Display->Views.