If you have any other events in your "LEM Internal Events" filter, what do their timestamps show? (How does it compare to the SNMP traps?)
The date is parsed from the log on the appliance (you can see it there - 20150528.163102), so (at least ) two things are possible -
1. appliance time was wrong (first guess)
2. maybe the connector isn't properly parsing things (also possible)