He probably thought the report missing the canary was published at the end of 2013 given that's the name of the report and the date in the filename. Understandable mistake.
The metadata in the PDF file says it was actually created on August 27th of this year.
I'm sure it could be found with a web archive or a quick search, but I personally believe it is irrelevant as it would not make sense to release the 2nd half 2013 report before the 1st half 2013 report. This means the 2nd half 2013 report had to have been released after Nov. 5, 2013, but beyond that, it wouldn't make sense to release the 2013 report before the year is over, would it? This leads me to believe it would be nearly impossible for this canary to have been missing for over a year.
Edit: ugh, hate when people edit after I already responded... It would literally be impossible for this canary missing to be over a year old. The news of the canary's existence didn't even break over a year ago (from my research).... I don't understand why this point is even debatable.
The metadata in the PDF file says it was actually created on August 27th of this year.