LSF exit codes don't necessarily line up with SAS return codes. We have had problems with LSF returning non-zero return codes but the SAS log is clean. I've found Googling LSF exit codes quite useful.
I would definitely not rely on LSF exit codes to indicate if the SAS job failed or not. To me there is no substitute for examining the batch SAS logs. Do you not have access to these as they just text files in a log folder.