Status Indian (Canada) who works 100% of the time on reserved work land but only for a partial year?

Does anyone have a Status Indian (Canada) who works 100% of
the time on reserved work land but only for a partial year?  He is 100% Status Indian Exempt in the Canadian
Tax Data panel effective September 2019.
When I test his T4, Box 71 is populating, but Box 20 Reg Pension Plan Contributions
and Box 44 Union Dues are showing as 0.
The employee did have Pension Plan Contributions and Union Dues
collected in the year, which is going to throw off the amount we used to calculate
Box 22 Income Tax Deducted.  How did you
handle this situation?  Thank you.