Update: received a response to webform complaint on CBSA website a couple months ago stating there are no derogatory comments on my file and that “we do no pre-flag anyone” 🙄

However, coincidence or not, the next time I crossed back into Canada via commercial carrier, lo and behold NO SECONDARY.

I have heard of similar reports where a complaint is submitted, CBSA denies everything, but somehow the issue ‘magically’ resolves.

Hope this post will prove useful for someone else in the future.