loadHTML只返回javascript，它不返回源

Question

I am trying to get HTML content of the page, but when I do that, my file_get_contents only returns piece of JS.

when I use just file_get_contents I can see the content but I am trying to use loadHTML as well. So using the function like below.

function getContent(String $url): \DOMDocument
    {
        $opts = array(
            'http' => array(
            'method'=>"GET",
            'header'=>"Content-Type: text/html; charset=utf-8"
            )
        );

        $context = stream_context_create($opts);
        $result = file_get_contents($url,false,$context);

        $parser = new \DOMDocument();
        $parser->loadHTML($result = mb_convert_encoding($result,'HTML-ENTITIES', 'ASCII, JIS, UTF-8, EUC-JP, SJIS'));

        return $parser;

    }

But this time, I am having DOMDocument::loadHTML(): Tag header invalid in Entity So tried to overcome this problem I used libxml_use_internal_errors(true); this but, then I am just returning JS part of page...

How can I overcome issue?

The links is here: https://lions-mansion.jp/MF161037/