Add dynamic sidebar in wp nav menu item

I've added a custom menu walker into my theme: 'walker' => new menu_walker

So i've created a navbar_widget function to insert dynamic sidebar at the end of menu item:

function navbar_widget() {
  if (function_exists('dynamic_sidebar')) {
  ob_start();
  dynamic_sidebar($item->sidebar);
  $out = ob_get_clean();
  return $out;
  }
}
add_filter( 'sidebar_filter', 'navbar_widget', 8 );

and i'm calling it in my menu_walker:

class menu_walker extends Walker_Nav_Menu  {
  function start_el(&$output, $item, $depth, $args) {
  ...
  $item_output .= ' </a>'.apply_filters('sidebar_filter', 'navbar_widget').''; 
  ...
  }
}

Everything is great when I'm using static name of dynamic sidebar like:

dynamic_sidebar('Sidebar1');

But I would like to use $item->sidebar to choose it dynamically in admin panel. When I insert dynamic_sidebar($item->sidebar); istead of apply_filters it displays a dynamic sidebar but above the menu.

EDIT: Maybe there is another way to add dynamic sidebar to menu item?

greetings