Add Taxonomies Dropdown Menu to Front End Event Editor

I’m trying to implement the following taxonomy (at very bottom of this post) into the event-editor.php file. I want my users to be able to select and add artists from a drop down menu on the front end editor. I can add the artists from the back end editor but have had no success from the front end. I’m mostly a front end developer so I don’t mess with PHP that much. Here’s what I have so far – which shows a drop down menu of different artists but fails to add or input them into the system when a user creates an event.

I duplicated categories-public.php and saved it as taxonomies-public.php with this code:

global $EM_Event;
/* @var $EM_Event EM_Event */
$categories = EM_Categories::get(array('orderby'=>'name','hide_empty'=>0));
?>
<?php if( count($categories) > 0 ): ?>
<div class="event-categories">
	<!-- START Categories -->
	<label for="event_categories[]"><?php _e ( 'Artists:', 'dbem' ); ?></label>
	<select name="event_categories[]" >
	<?php
	$taxonomies = array('artists');
		$args = array('orderby'=>'count','hide_empty'=>true);
		echo get_terms_dropdown($taxonomies, 0, $args);
	?></select>
	<!-- END Categories -->
</div>
<?php endif; ?>

CUSTOM TAXONOMY CODE – I’ve put this into its own plugin file.

// custom Artist taxonomy for events
add_action( 'init', 'register_my_taxonomies', 0 );

function register_my_taxonomies() {
$labels = array(
    'name'                          => 'artists',
    'singular_name'                 => 'artist',
    'search_items'                  => 'Search Artists',
    'popular_items'                 => 'Popular Artists',
    'all_items'                     => 'All Artists',
    'parent_item'                   => 'Parent Artist',
    'edit_item'                     => 'Edit Artist',
    'update_item'                   => 'Update Artist',
    'add_new_item'                  => 'Add New Artist',
    'new_item_name'                 => 'New Artist',
    'separate_items_with_commas'    => 'Separate Artists with commas',
    'add_or_remove_items'           => 'Add or remove Artists',
    'choose_from_most_used'         => 'Choose from most used Artists'
    );

$args = array(
    'label'                         => 'Artists',
    'labels'                        => $labels,
    'public'                        => true,
    'hierarchical'                  => true,
    'show_ui'                       => true,
    'show_in_nav_menus'             => true,
    'args'                          => array( 'orderby' => 'term_order' ),
    'rewrite'                       => array( 'slug' => 'events/artists', 'with_front' => false ),
    'query_var'                     => true
);

register_taxonomy( 'artists', EM_POST_TYPE_EVENT, $args );
}

// custom taxonomy search and display
add_action('em_template_events_search_form_ddm', 'artists_search_form');
function artists_search_form(){
	$artists = (is_array(get_option('artists'))) ? get_option('artists'):array();
	?>
	<!-- START artists Search -->
	<select name="artist" id="artist_search">
		<option value="" selected="selected">Artists</option>
		<?php
		$taxonomies = array('artists');
		$args = array('orderby'=>'count','hide_empty'=>true);
		echo get_terms_dropdown($taxonomies, $args);
		?>
	</select>
	<!-- END artists Search -->
	<?php
}

function my_em_artists_event_load($EM_Event){
	global $wpdb;
	$EM_Event->artists = $wpdb->get_col("SELECT term_taxonomy_id FROM $wpdb->term_relationships WHERE object_id='{$EM_Event->post_id}'", 0	);
}
add_action('em_event','my_em_artists_event_load',1,1);

// And make the search attributes for the shortcode
add_filter('em_events_get_default_search','my_em_artists_get_default_search',1,2);
function my_em_artists_get_default_search($searches, $array){
	if( !empty($array['artist']) ){
		$searches['artist'] = $array['artist'];
	}
	return $searches;
}

add_filter('em_events_get','my_em_artists_events_get',1,2);
function my_em_artists_events_get($events, $args){
	if( !empty($args['artist'])  ){
		foreach($events as $event_key => $EM_Event){
			if( !in_array($args['artist'],$EM_Event->artists) ){
				unset($events[$event_key]);
			}
		}
	}
	return $events;
}

function get_terms_dropdown($taxonomies, $args){
	$myterms = get_terms($taxonomies, $args);

	foreach($myterms as $term){
		$root_url = get_bloginfo('url');
		$term_taxonomy=$term->taxonomy;
		$term_slug=$term->slug;
		$term_name =$term->name;
		$value = $term->term_id;
		$output .="<option value='".$value."'>".$term_name."</option>";
	}

return $output;
}

Any help would be greatly appreciated. Thanks!!

https://www.ads-software.com/extend/plugins/events-manager/