Hi Rohan,
Good to know that you are able to see data for Network Received and Network Transmitted counters.
For External Network transfer and External Network Receive counters. Few more points.
This is from chargeback 1.5 user guide.
The vShield Manager Data Collector fetches the external traffic information from vShield Manager for the
Moreover are you seeing any IP address under the network (see attached image)? If you are not seeing IP address then the network statistics will not come.
If nothing works can you please attach vsm-dc log files (the latest one).
-Amrainder