Sadly, Pilecki was killed by the fellow Poles, not by Soviet Russians. The article you quoted makes goes even as far as to distort the reality:
> His Soviet prosecutor, Czesław Łapiński, died on the way to the hospital, before his trial for judicial murder.
This person wasn't Soviet - he was a Pole, born in Silesia, a Polish soldier fighting the Nazi. I know it's more convenient to portray it as "the Russians were guilty of all wrong", but the reality is that during the Stalinist rule many atrocities were committed by Poles on Poles.
This point o view is actually present in the official version of the history as taught in many countries, with a notable exception of Germany: one's own country is always portrayed at its best, and its citizens as good fellows. The idea that one's ancestors might commit many atrocious crimes is terrifying. Yet, it is often the case. In this particular situation, some people were motivated by greed, some by their survival instinct, but some were just firm believers in Communism and were convinced they do the right thing. To them, Pilecki was just a bandit and a traitor. It's important to be aware of that, because this lesson from the past has bearing on present and future, for whoever is able to reason and draw conclusions.
Please keep nationalistic flamewar off HN. This is a highly international community and the last thing we need is old regional resentments breaking out all over the place.
I think that pointing out that Soviet atrocities were worse than Nazi atrocities (and Maoist atrocities were worse still) isn't a matter of 'regional resentments' but of ground truth.
Of his imprisonment under the Soviets he told his wife:
"I cannot live. They killed me. Because compared to them Auschwitz was just a trifle."
[1] - http://www.poloniainstitute.net/witold-pilecki-bravery-beyon...
[2] - https://www.warhistoryonline.com/world-war-ii/story-of-the-m...