this is the closest I have found.
Apparently, if you have Application & Device policies enabled, you can read the recorded USB activities from the AGENT_BEHAVIOUR_LOG tables. We currently don't use ADC, so this is just a simplistic sample.
SELECT * FROM AGENT_BEHAVIOUR_LOG_1
UNION
SELECT * FROM AGENT_BEHAVIOUR_LOG_2
ORDER BY TIME_STAMP
if you need more details build you own query from the schema.
Symantec Endpoint Protection 12.1.6 database schema