WordPress shortcode issues with output

Hi I am trying to workout how to use shortcodes on a plugin but I am stuck with this .. Its a plugin I found on http://www.wpbeginner.com/wp-tutorials/how-to-add-rotating-testimonials-in-wordpress/

It is working a little but not outputting the code correctly and not sure why this is happening.

I Have upgraded the code and removed the css and jquery code as I will add this separate files..

Any help will be great!

<?php



/*



Plugin Name: Shortcode test
Version: 0.1
Plugin URI: http://www.websiteplugin.com/
Description: Adding theatre edits to the resume page
Author: Auther name
Author URI: http://www.websiteauther.com/



*/







add_action( 'init', 'wpb_register_cpt_testimonial' );







function wpb_register_cpt_testimonial() {







$labels = array(



'name' => _x( 'Testimonials', 'testimonial' ),
'singular_name' => _x( 'testimonial', 'testimonial' ),
'add_new' => _x( 'Add New', 'testimonial' ),
'add_new_item' => _x( 'Add New testimonial', 'testimonial' ),
'edit_item' => _x( 'Edit testimonial', 'testimonial' ),
'new_item' => _x( 'New testimonial', 'testimonial' ),
'view_item' => _x( 'View testimonial', 'testimonial' ),
'search_items' => _x( 'Search Testimonials', 'testimonial' ),
'not_found' => _x( 'No testimonials found', 'testimonial' ),
'not_found_in_trash' => _x( 'No testimonials found in Trash', 'testimonial' ),
'parent_item_colon' => _x( 'Parent testimonial:', 'testimonial' ),
'menu_name' => _x( 'Testimonials', 'testimonial' ),



);


$args = array(



'labels' => $labels,

'hierarchical' => false,

'supports' => array( 'title', 'editor', 'excerpt', 'author', 'thumbnail', 'custom-fields', 'revisions' ),
'public' => true,
'show_ui' => true,
'show_in_menu' => true,
'show_in_nav_menus' => true,
'publicly_queryable' => true,
'exclude_from_search' => false,
'has_archive' => true,
'query_var' => true,
'can_export' => true,
'rewrite' => true,
'capability_type' => 'post'



);

register_post_type( 'testimonial', $args );

}

$key = "testimonial";

$meta_boxes = array( 

"person-name" => array(
"name" => "person-name",
"title" => "Person's Name",
"description" => "Enter the name of the person who gave you the testimonial."),
"position" => array(
"name" => "position",
"title" => "Position in Company",
"description" => "Enter their position in their specific company."),
"company" => array(
"name" => "company",
"title" => "Company Name",
"description" => "Enter the client Company Name"),
"link" => array(
"name" => "link",
"title" => "Client Link",
"description" => "Enter the link to client's site, or you can enter the link to your portfolio page where you have the client displayed.")


);


function wpb_create_meta_box() {



global $key;


if( function_exists( 'add_meta_box' ) ) {



add_meta_box( 'new-meta-boxes', ucfirst( $key ) . ' Information', 'display_meta_box', 'testimonial', 'normal', 'high' );



}



}


function display_meta_box() {

global $post, $meta_boxes, $key;



?>

<div class="form-wrap">

<?php



wp_nonce_field( plugin_basename( __FILE__ ), $key . '_wpnonce', false, true );


foreach($meta_boxes as $meta_box) {

$data = get_post_meta($post->ID, $key, true);



?>


<div class="form-field form-required">

<label for="<?php echo $meta_box[ 'name' ]; ?>"><?php echo $meta_box[ 'title' ]; ?></label>

<input type="text" name="<?php echo $meta_box[ 'name' ]; ?>" value="<?php echo (isset($data[ $meta_box[ 'name' ] ]) ? htmlspecialchars( $data[ $meta_box[ 'name' ] ] ) : ''); ?>" />



<p><?php echo $meta_box[ 'description' ]; ?></p>



</div>


<?php } ?>


</div>



<?php



} 

function wpb_save_meta_box( $post_id ) {

global $post, $meta_boxes, $key;

foreach( $meta_boxes as $meta_box ) {



if (isset($_POST[ $meta_box[ 'name' ] ])) {



$data[ $meta_box[ 'name' ] ] = $_POST[ $meta_box[ 'name' ] ];



}



}


if (!isset($_POST[ $key . '_wpnonce' ]))

return $post_id;

if ( !wp_verify_nonce( $_POST[ $key . '_wpnonce' ], plugin_basename(__FILE__) ) )

return $post_id;

if ( !current_user_can( 'edit_post', $post_id ))

return $post_id;

update_post_meta( $post_id, $key, $data );



}

add_action( 'admin_menu', 'wpb_create_meta_box' );
add_action( 'save_post', 'wpb_save_meta_box' );


function wpb_display_testimonials() { 


$return_string .= "<div id="testimonials">";


$args = array( 'post_type' => 'testimonial', 'posts_per_page' => 100, 'orderby' => 'menu_order', 'order' => 'ASC' );

$loop = new WP_Query( $args );


if ( $loop->have_posts() ) : while ( $loop->have_posts() ) : $loop->the_post();

$data = get_post_meta( $loop->post->ID, 'testimonial', true );

static $count = 0;


if ($count == "1") { 

$pn_data = $data[ 'person-name' ];

$p_data = $data[ 'position' ];

$l_data = $data[ 'link' ];

$c_data = $data[ 'company' ];

$con_the = get_the_content( $more_link_text, $stripteaser );

$return_string .= '<div class="slide" style="display: none">



<div class="client-contact-info">'; $return_string .= $pn_data; $return_string .=',&nbsp;'; $return_string .= $p_data; $return_string .=',&nbsp;<a href="'; $return_string .= $l_data; $return_string .='" title="'; $return_string .= $c_data ; $return_string .= '">'; $return_string .= $c_data ; $return_string .='</a></div>';



$return_string .= '<div class="clear"></div>



<div class="testimonial-quote">'; $return_string .= $con_the; $return_string .='</div>



</div>';



}
else { 


$pn_data = $data[ 'person-name' ];

$p_data = $data[ 'position' ];

$l_data = $data[ 'link' ];

$c_data = $data[ 'company' ];

$con_the = get_the_content( $more_link_text, $stripteaser );



$return_string .= '<div class="slide" >

<div class="client-contact-info">'; 

$return_string .= $pn_data; 

$return_string .=',&nbsp;'; 

$return_string .= $p_data;

$return_string .=',&nbsp;<a href="'; 

$return_string .= $l_data;

$return_string .='" title="'; 

$return_string .= $c_data ; $return_string .= '">'; 

$return_string .= $c_data ; $return_string .='</a></div>';

$return_string .= '<div class="clear"></div><div class="testimonial-quote">';

$return_string .= $con_the; 

$return_string .='</div></div>';


$count++; 

}



endwhile;



endif;

$return_string .='</div>';

return $return_string;




}



function register_shortcodes(){

add_shortcode('testme', 'wpb_display_testimonials');

}

add_action( 'init', 'register_shortcodes');



?>