Poles? LOL no. They don't have the capability, or the motive.
The motive was to remove the ability of the Germans to ask Russia to turn the gas back on when they're freezing in the dark in another month or two. We all know that Nordstream 2 was finished, right? And the only reason it's not operating is because Germany demanded it be turned off. In a moment of weakness, Germany might well bend the knee to Russia and ask pretty please to turn the gas back on. The CIA must never allow this. Thus, the mysterious pipeline explosion that obviously Russia did, despite the fact that Russia has zero incentive to destroy billions of dollars of infrastructure and would like very much to turn the pipe on and start selling gas to Germany.
Always ask: who benefits?
Nah, Poland doesn't have the motive, or capability. But you know who does? The Americans.
If Poland had a motive it would reopen the pipeline that crosses its territory. And the capability? Please. All they have the capability to do is incompetently maintain their airplanes so one crashes with the prime minister and most of the government in it.