When TargetServerID is set, the TargetJob may be null. In that case you can obtain the identity and name from the TargetJobOID and TargetJobName. If you need a reference to the job, you must make a separate connection to the TargetComputer and retrieve the job.
If the target job is on a different adTempus instance, setting TargetJob automatically sets the TargetJobOID, TargetServerID, and TargetComputer.