The seq_item_port is a specific type of port which allows bi-directional communication between the sequencer and driver. There are several additional methods provided by it which enable sequences to function.
You should never have a need to connect a scoreboard monitor with a sequencer. A sequence is used only for stimulus generation, whereas the monitor is use for determining correctness. If you need information concerning transaction completion, use the bi-directional capability of the seq_item_port.