Activity End Date on Certificates

It would be great to have a certificate template field 'Activity End Date' from the Result Outcomes for our eLearn courses (not hosted in Axcelerate). In these instances our Course End Date is not the same as the date the student finishes the course and to get the accurate date, you need to go in and override the End Date in the workshop per student. We've added a custom field workaround but it would be great if you could have the Activity End Date as an option to pull onto the certificate for printing.