Vontu Email prevent catch (block) and release capbility

I am trying to investigate how to set up Vontu prevent for email so when certain emails hit a policy they are blocked and then we can check with management and then go into the system and  release the email to continue to its destination. I know that Symantec DLP cannot do this natively, does anyone have experience with another Symantec product or  3rd party system that could work with DLP and provide catch and release capability? Thanks