I don't pretend to know CFL. rules, but that might be the worst DPI call in the history of football. I should know... two of mine round out the top 3. Thankfully, mine were on a smaller stage.
The general rules are almost exactly the same, with one proviso: in Canadian, a stationary defender may defend a space he occupies, generally in a one-step zone.
And this makes my worst blown PI call look like peanuts. Feel forry for the guy, but as a chap on the university bubble, I have faith in the process that keeps the good guys on the field.