[Chadi]

That's because Usercount is supposed to be UserCount (case sensitive)

http://147.202.66.3:8085/?api.UserCount

The exact code in that rcplugin.php page is this:

<?php
    function getAPI($command) {
        $er = error_reporting(0);
        $result = file_get_contents("http://147.202.66.3:8085/?api.".$command);
        error_reporting($er);
        return $result;
    }
     
    echo "Number of users: ".getAPI("UserCount")."<br/>";
    echo "Rooms available: ".getAPI("RoomList"); 
?>