How to search for posts IN OR title OR content OR author?

I have looked at many posts and questions regarding searches for custom meta, but I want to search for posts and include those if the search query matches an author name.

I have come up with the following code but it is not working. For some reason, it returns posts with status "revision"

First, I hooked my three functions to their respective hooks:

add_filter('posts_join', 'custom_posts_join' );
add_filter('posts_groupby', 'custom_posts_groupby' );
add_filter('posts_where', 'custom_posts_where' );

Then, I proceed with each function:

custom_posts_join

function custom_posts_join($join){
    global $wpdb;
    if( is_search() && !is_admin()) {

        $join .= " LEFT JOIN $wpdb->postmeta ON $wpdb->posts.ID = $wpdb->postmeta.post_id ";
    }
    return $join;
}

custom_posts_groupby

function custom_posts_groupby( $groupby ) {
    global $wpdb;
    if( is_search() && !is_admin()) {

        $groupby = "$wpdb->posts.ID";
    }
    return $groupby;
}

custom_posts_where

function custom_posts_where( $where = '' ){
    if ( is_search() && !is_admin()) {
        global $wpdb;

        $search = ( isset($_GET["s"]) ) ? sanitize_text_field($_GET["s"]) : false ;
        $search = (string)$search;

        $users = $wpdb->get_results( "SELECT user_id FROM $wpdb->usermeta WHERE meta_key = 'first_name' AND meta_value = '$search'",OBJECT_K  );

        foreach ($users as $user)
        {
            $users_ids.=$user->user_id.','; 
        }
        $users_ids = rtrim($users_ids, ',');

        $where .= " AND ( ($wpdb->posts.post_author IN ({$users_ids})) 
               OR ($wpdb->posts.post_title LIKE '$search')
               OR ($wpdb->posts.post_content LIKE '$search') )
            AND $wpdb->posts.post_type = 'post'
            AND $wpdb->posts.post_status = 'publish'";  

        }
    return $where;
}