Completed data set registrations and "storedby"

Hi there.

I am putting together a custom script to handle the calculation of
mobile credit which will be disburse to mobile reporters, based on
their timely reporting. Without delving into the details, I need to
know who actually completed the
dataset,but it seems when I look at the "completeddatasetregistration"
object, this field is not recorded for the mobile reporters when they
complete the dataset. Is this maybe a blueprint or bug?