There was another famous accident attributed to the lack of de-icing, in 1989, in Dryden, ON.
What strikes me as similar to the incident described in this thread is that in the Dryden accident, a flight attendant, as well as two non-revving pilots, noticed a significant amount of snow on the wings.
However, the f/a decided not to express her concerns to the captain, because of adverse reactions by other company pilots in the past when she had expressed similar concerns. (The crew was also late departing, and had been away from home for six days.)*
The other thing that I noticed is that both the Dryden accident and the subject incident of this thread happened in Canada.
I wonder if, as a result of Dryden, ground staff in Canada have been trained to keep a keener eye peeled for aircraft attempting to depart with potentially contaminated wings, which would have possibly triggered the irregularity report.
Pure speculation on my part, of course.
* (Source: "The Dryden Accident" from "Single Pilot CRM", by Phil Croucher, Lulu.com, 2005)