PHP scraping information from another URL, Blank page or E_NOTICE : type 8 -- Trying to get property of non-object

Question

basically I'm trying to make a small tracking plugin for my website, and I'm not sure what I am meant to put get the correct name for the element ID. I either get a blank screen or E_NOTICE : type 8 -- Trying to get property of non-object

I just want to display this

https://puu.sh/EItml/34bdb97863.png

Here was the first I tried...

    include('simple_html_dom.php');

    $html = file_get_html('https://www.auspost.com.au/mypost/track/#/details/63243842914091');

    echo $html->find('title', 0)->plaintext;

    $list = $html->find('div[class="event-header"]',0);

    $list_array = $list->find('a');

    for( $i = 0; $i < sizeof($list_array); $i++ ){
        echo $list_array[$i]->plaintext;
        echo "<br>";
    }

?>

and the second

    include('simple_html_dom.php');

    $html = file_get_html('https://www.auspost.com.au/mypost/track/#/details/63243842914091');

    echo $html->find('title', 0)->plaintext;
    echo $ret = $html->find('event-location', 0)->plaintext;



?>

I did do some research but I'm unsure as to what I need to put, sorry if this is a timewaster, I'm just new to PHP...

Here's of where its located on the URL

https://puu.sh/EItlK/671f9877ed.png

https://puu.sh/EIt9C/be30180469.png

TIA :)