RSS Feed Validation Problem

Here is what the feed validator shows me:

This feed does not validate.

line 7, column 0: XML parsing error: <unknown>:7:0: not well-formed (invalid token)

Source: https://www.employmentblawg.com/wp-rss-feedburner.php

   1. <?xml version="1.0" encoding="UTF-8"?><!-- generator="wordpress/2.2" -->
   2. <rss version="2.0"
   3. xmlns:content="https://purl.org/rss/1.0/modules/content/"
   4. xmlns:wfw="https://wellformedweb.org/CommentAPI/"
   5. xmlns:dc="https://purl.org/dc/elements/1.1/"
   6.
   7. <channel>

Yet, my wp-rss-feedburner.php actually is:

<?php
if (empty($feed)) {
	$blog = 1;
	$feed = 'rss2';
	$doing_rss = 1;
	require('wp-blog-header.php');
}

header('Content-type: text/xml; charset=' . get_settings('blog_charset'), true);
$more = 1;

?>
<?php echo '<?xml version="1.0" encoding="'.get_settings('blog_charset').'"?'.'>'; ?>
//generator="wordpress/<?php bloginfo_rss('version') ?>"

<rss>

<channel>

Why the discrepancy? It’s not a plugin because I’ve disabled them all. I’ve deleted the php file, tried to validate it, and it correctly shows that it’s missing. However, when I re-upload the file it reverts it back to the erroneous file. What in the world could be doing this?