At this point the issue is with this recordset:
$query_Employees = "SELECT * FROM Users WHERE ID IN (".$row_UsersMachines['EmpID'].")";
$Employees = mysql_query($query_Employees, $con1) or die(mysql_error());
$row_Employees = mysql_fetch_assoc($Employees);
$totalRows_Employees = mysql_num_rows($Employees);
But I'm not sure what you are trying to do there... what did you expect to get for the final SQL statement in this case?
SELECT * FROM Users WHERE ID IN ([what shoudl be here?])