You would like to understand what are the differences between EUR module and the standard DLP incident management module in Service Now?
Component: Data Loss Prevention
The DLP Incident Response integration with Symantec is for incident remediators responding to an incident through an automated way like an email.
The other Symantec DLP End User Remediation is as it sounds, it's the end-user who manages their own incident allowing them to respond and manage their own incident - see About End User Remediation