PHP parse error causes 500 server error

Hello,

One day our WordPress-app stopped working. Both the admin-view and the visitor’s view started showing HTTP ERROR 500.

I happen to be a software developer, but my understanding about servers and the WordPress-application is limited.

The website is for an organization that I am a apart of. We have lost contact to the person who originally set up our website. Troubleshooting this issue now falls to me.

Every time the site is visited, this error is printed to the error log:

[02-Apr-2018 17:42:45 UTC] PHP Parse error: syntax error, unexpected ‘*’ in /home/[censored]/public_html/wp/wp-includes/load.php on line 580

The error gets logged only when visiting the main website. The error does not get logged when attempting to visit the admin-view.

This is the line that the error message is pointing to (the 580th line):

if ( $wp_filter )

Here is the entire function:

https://pastebin.com/4CZshCYS

The word press version we are running is 4.9.4. I looked it up from version.php

I have ran many fix attempts. All of the fixes in this article made no difference:

https://wordpress.org/support/topic/http-error-500-internal-server-error-21/

I ran the htacess fix, disabling themes and disabling plugins.

I tried uploading new wp-includes and wp-admin from a clean install of word press, as this article suggested:

http://www.wpbeginner.com/wp-tutorials/how-to-fix-the-internal-server-error-in-wordpress/

Of course, I can’t promise if I have done all of the fixes correctly. I can try them again on upcoming days, if needed. My service provider is vlexoFree (I believe). They provide a cPanel interface, but I’m not very good at using it. I even failed at trying to find the server version :/. I will add more information to this thread later.

I am not certain what to do next. I would be very grateful if someone could offer advice. Thank you.