add_filter("gform_pre_render_6", "populate_event_metaCreators");

function populate_event_metaCreators($form){
    $postOptions = NULL;

    foreach($form['fields'] as &$field) {
        switch ($field['inputName']) {
            case 'OrganizerSelect':

                global $wpdb;
                $postOptions = $wpdb->get_results
                ("SELECT ID, post_title FROM $wpdb->posts where post_type = 'tribe_organizer' and post_status = 'publish' order by post_title ASC");

                break;

            case 'VenueSelect':

                global $wpdb;
                $postOptions = $wpdb->get_results
                ("SELECT ID, post_title FROM $wpdb->posts where post_type = 'tribe_venue' and post_status = 'publish' order by post_title ASC");

                break;
        }

        if($postOptions != NULL) {
            $choices = '';
            $choices[] = array('text' => '', 'value' => '', 'isSelected' => '', 'price' => '');
            $choices[] = array('text' => 'Add New Entry', 'value' => 'Add New Entry', 'isSelected' => '', 'price' => '');

            foreach ($postOptions as $postOption) {
                $choices[] = array('text' => $postOption->post_title, 'value' =>  $postOption->ID, 'isSelected' => '', 'price' => '');
            }
            $field['choices'] = $choices;

            $postOptions = NULL;
        }

    }

    return $form;
}