I'm sure the information is in the core dump somewhere, but there is no easy way to locate the values.
If the issue is reproducible, then you should be able to setup the log file and replicate the failure. If its a one time failure then it could be anything and potentially not even anything related to your application.
I would setup a log file then watch for the problem to resurface.
One simple technique for the log file is add logic like:
DayNo = JUL(0,0,0)
P$ = "/tmp/pxpluslog."+dte(DayNo +1:"%Ws")
P$ = "/tmp/pxpluslog."+dte(DayNo :"%Ws")
SETDEV (0) SET "LogFile" TO P$
This will create you a daily log file with the day of the week in its name and keep the last 6 (requires the logic to run at least once per day every day).