[Theme: tanzaku] random post order in the grid is not working on main page (only on single post)

hello all,

my problem is, that the random sort order for the posts is not working on the main page grid, but it works on the single post site-grid. i don’t use any plug-ins and used the following code for the grid items:

<!-- grid items-->
<?php /* make a new query for grid items (in single page) */
	  	$new_query_arg = 'paged='.$paged;
		$args = array(
    	'orderby' => 'rand',
		'numberposts' => 100,
		);

	// use this code if you want filter items by category.
	/* $arr_catID = array();
	foreach( get_the_category() as $cat) $arr_catID[] = $cat->cat_ID;
	if ( count($arr_catID) ) $new_query_arg .= '&cat=' . join(',', $arr_catID);
	*/

	remove_all_filters('posts_orderby');
	query_posts($args);
?>

do i have to add the random order also for the query of the single wrapper? if so, please explain me how, because i am not a wordpress-pro.
thx!

https://www.ads-software.com/extend/themes/tanzaku/