Does anyone know a way to default values for missing XML tags?

Summary

HCM Extract doesn't create empty XML tags for child records

Content

The vendor requires us to provide a default value in a fixed position if the employee has no payroll earnings for the period.  Since payroll results is a child record, HCM Extract does not produce the empty XML tags.

We are using eText to produce the fixed position output file, which cannot interrogate for empty tags.  Without a tag, we cannot provide the default.

Is there a way to force the tag to be created in HCM Extract or provide the default value in eText?

We are using OIC to orchestrate the process, so if there's a way to do this in that tool I would like to know.