替换代码标记之间的<和>不起作用

I took the answer from this question, and modified it to my needs a bit, but it's not working obviously.

The plugin I'm modifying, has a function that will 'preclean' the content using the function

function aiosc_preclean_content($string) {

    $rplc = array(
        "\\'"=>"'",
        '\\"'=>'"',
        "\\\\"=>"\\",
    );

    return str_replace(array_keys($rplc),array_values($rplc),$string);
}

This looks for quotes and multiple backslashes and replaces them. Function works fine so I wanted to modify it so that anything inside <code> tags (html in particular) that has < and > will be replaced by < and >

First I tried the original answer, didn't work. Then I tried my own:

function aiosc_preclean_content($string) {

    $rplc = array(
        "\\'"=>"'",
        '\\"'=>'"',
        "\\\\"=>"\\",
        "‘"=>"'",
        "’"=>"'",
        "“"=>'"',
        "”"=>'"',
    );

    $pre_returned_content = str_replace(array_keys($rplc),array_values($rplc),$string);
    $text = preg_replace_callback("~<code>(.*?)<\/code>~",'replaceInCode',$pre_returned_content);
    // $new_content = htmlspecialchars($text);
    return $text;
}

function replaceInCode($match){
    $replace = array('<' => '&lt','>' => '&gt');
    $text = str_replace(array_keys($replace),array_values($replace),$match[1]);
    return $text;
}

I added the curly quotes as a prereplace check. Now the problem with this is that it will turn the <code> tags in <code> which is not good at all (I need the <code> tags for the code to work properly).

What am I doing wrong here? I tried adding <code> tags around the returned text in the callback function for preg_replace_callback, but that didn't work as well.

EDIT: The weird part is when I try this in sandbox online it works :\

EDIT2

I tried this as well (there is another cleaning function that stips tags)

function aiosc_clean_content($string,$html_tags="", $autop = true) {
    $string = aiosc_preclean_content($string);
    if(empty($html_tags)) $html_tags = "<b><strong><em><i><br><hr><p><span><small><h1><h2><h3><h4><h5><ul><ol><li><a><del><blockquote><pre><code><script>";

    $string = strip_tags($string,$html_tags);
    if($autop) $string = wpautop($string);

    $text = preg_replace_callback("~<code>(.*?)<\/code>~",'replaceInCode',$string);

    return $text;
}
function aiosc_preclean_content($string) {
    $rplc = array(
        "\\'"=>"'",
        '\\"'=>'"',
        "\\\\"=>"\\",
        "‘"=>"'",
        "’"=>"'",
        "“"=>'"',
        "”"=>'"',
    );
    return str_replace(array_keys($rplc),array_values($rplc),$string);
}

function replaceInCode($match){
    $replace = array('<' => '&lt;','>' => '&gt;');
    $text = str_replace(array_keys($replace),array_values($replace),$match[1]);
    return '<code>'.$text.'</code>';
}

Still nothing.