Hello,
I've used ST03 or other transactions in the past to access the system log to see what users have been doing.
But in your case it looks like the problem is with a workflow being stated when it shouldn't be. Even if you find out why that is happening (could be a timing issue - the object may not exist yet) you may want to build in a condition in SWB_COND (as suggested by Rob) to stop the workflow from being started.
Is this a Production issue?
regards
Rick