with site move server 500 related to wordfence-waf.php

1. I have moved my newly built website from dev.birtafoto.hu (folder websites/dev.birtafoto.hu) to birtafoto.hu (folder public_html).
2. As usual, I have replaced the URLs, I have used velvet URL plugin.
3. changed the site name, site url in the wp_options table
When I try to get rid of (or just rename) the old folder of the website (/websites/dev.birtafoto.hu) the site crashes with a server 500 error.

It turns out that the old wordfence-waf.php file causing the issue.
I have removed wordfence plugin from the site at its new place – dropping all db tables as well. but the problem still exists.

I have done what you have suggesting on other threads:
edited .htaccess with this code:

# Wordfence WAF
<Files ".user.ini">
<IfModule mod_authz_core.c>
Require all denied
</IfModule>
<IfModule !mod_authz_core.c>
Order deny,allow
Deny from all
</IfModule>
</Files>
# END Wordfence WAF

i have edited user.ini:
; Wordfence WAF
auto_prepend_file = ‘/mysite/wordfence-waf.php’
; END Wordfence WAF

interestingly the wordfence with the new install with new tables still pointed to the old url in the user.ini and the wordfence-waf.php files (I have corrected this as well). why is that?
but no matter I have corrected the paths the problem still persists.

how can I get rid of the old wordfence-waf file at the old folder? That is the one which is causing the hwole issue.

Thanks for your help.

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