Trying to echo posts of author on user page

I am trying to echo all author posts for each user as URLs with user_id as the author id in a custom column within the User List table (User.php)… not sure what is wrong.. Thanks!

function new_modify_user_table_send_inv( $column ) {
    $column['send_inventory'] = 'Email Inventory';
    return $column;
}
add_filter( 'manage_users_columns', 'new_modify_user_table_send_inv' );

function new_modify_user_table_row_send_inv($custom_column, $column_name, $user_id ) {
	if ($column_name=='send_inventory') {
			$posts = get_posts(array('author'=>$user_id));
			$custom_column = array();
			if(isset($posts) && !empty($posts))
				foreach($posts as $post){
					$custom_column[] = "<li>".$post->post_title."</li>";
				}
			$custom_column = implode("\n",$custom_column);
	}
	return $custom_column;
}
add_filter( 'manage_users_custom_column', 'new_modify_user_table_row_send_inv', 10, 3 );