On the Export screen, each TimeClock Payroll Code must have a correlating QuickBooks Payroll Item.
Click Settings > Reason Codes. Select each Payroll Code Description individually. For each one, look in the upper-right corner. It should look similar to the image below. There must also be a Payroll Code Number.
NOTE: A Related Attendance Absence Code is only necessary when using this in conjunction with Gradience Attendance.
Timing is everything!
This relationship cannot be established after-the-fact. [After] this relationship has been established, You must create a NEW Time Card Run that is identical to the one that failed but because this second run is created [after-the-fix] It will export successfully from Gradience and import successfully into QuickBooks.