Either the article writer is confusing Norway with another country or this is just "Journalistic flair" i.e. a lie.
Why do you say this journalist is lying, but lack of evidence from other journalists must mean this one is wrong?
Pirate Bay is a big site, and journalists and the population would notice. But they might not know to look for other sites being censored. Just food for thought. I don't know whether to believe it either, but I'm willing to leave it to others to fact check more rigorously.
A perfectly reasonable explanation that obeys all the facts could be that a single telecom blocked access for a short time by mistake, was alerted, and silently fixed it before journalists noticed. I doubt many people are visiting hrw.org on a daily basis, and an outage like that could be mistaken for temporary website issues. A journalist would probably not assume it was a country-wide block and so wouldn't think to write an article about it.
It's possible that it was a mistake, and corrected, but it should still concern you that it was done to begin with.
Telecoms should not be the arbiters of what content you view.