Some strange things happening here...
The first require cannot work.
WB_PATH is only set in the config.php that is required_once. So if WB_PATH is defined, the config is already loaded making that line useless.
If not, it will effectively load [SERVER_ROOT]/config.php which is very unlikely to succeed.
The second require is not part of WB, so no telling what will happen there.
The third require is useless too. The same thing as the first one, if WB_PATH is defined, config.php is loaded and the WB initialize script is called too. With that the database classes are already loaded.
The command "load_website_config()" is not a WB function. No telling what should happen there.
So for an external script, just load config.php (make shure your script knows where it is located).
After that, the $database functions are available to that script.