To find all single-event calls in your queue_log you can run the following query:

SELECT call_id, count( * ) , verb
FROM queue_log
WHERE partition = 'P001'
AND verb NOT IN (
'AGENTCALLBACKLOGIN', 'AGENTCALLBACKLOGOFF', 
'AGENTLOGIN', 'AGENTLOGOFF', 
'ADDMEMBER', 'REMOVEMEMBER', 
'PAUSEREASON', 'CALLSTATUS'
)
GROUP BY call_id
HAVING count( * ) = 1

Change the partition as you see fit. Then you should delete them by call-id.