Execute custom php file outside /pub folder in Magento2 Nginx

I would like to execute a custom php file (required for a validation and scan) on our Magento2 installation. The file however should remain and be located in the main /var/www/html/ folder and not in the /var/www/html/pub/ folder.

I have tried the following in my main vhost configuration but still getting a 404

    location /mycustomfile.php {
        try_files $uri $uri/;
        location ~* \.php$ {
        fastcgi_pass fastcgi_backend;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
        }
    }

Also I have seen to "whitelist" the file in /var/www/html/nginx.conf.sample under:

    # PHP entry point for main application
    location ~ 
  
    (index|get|static|report|404|503|health_check|mycustomfile)\.php$ {

Some expert help would be greatly appreciated, thank you!

EDIT:

Okay I figured it out:

    location /mycustomfile.php {
        try_files $uri $uri/;
        root /var/www/html;
        location ~* \.php$ {
        fastcgi_pass fastcgi_backend;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
        }
    }