Hello,
You can't add exceptions to the Network Shares Monitoring based on Name structure and DLP does not support IP filter for Network shares.
It means that you can control all network shares the same way or not control any (when activating the network shares in the agent config monitoring).
I have been told by Symantec that this is a known issue. The Product Management team have already opened an Enhancement request on this issue. Enhancement Request PM-1685.
Best regards,
Morgado