Hi aroundwrd99.
When I left Canada in 2011, I got a "departure order became a deportation order" because I did not leave Canada within 30 days of the day the departure order was issued. Basically my refugee was rejected (including H&C, Federal Court Appeal and Praa). So this is why the Visa office requested the ARC form.
If you left Canada under Departure Order (form number IMM 5238), you don't require an ARC.
Otherwise, if CBSA gave you a Departure order become a deportation order, you will require an ARC.