Yes, but it also says current consumption <100uA. Obviously the >5uA gives you a hint about the capabilities of the module. If it could drive 500uA they would have written it. This kind of module is designed to go into a clock --> low current consumption is a design goal, extended driving capability is not. --> I would be very suprised if it would be able to drive 500uA. This is the reason why I bought one with additional driver transistors.