Just some speculation

so we have this picture https://files.catbox.moe/th432q.png

(https://greatawakening.win/p/16ZE00PNZf/)

to me these pieces look quite similar to a solid rocket booster used on S-200

https://files.catbox.moe/c7lcze.jpg

(Picture from: Military History Museum of the Air Forces of the Armed Forces of Ukraine, think of it what you want)

anyway

1. It is anti-air

2. It is fired from ground based platform

3. Russia is no longer using these since 2014 (according to wiki)

4. Solid-fueled booster would not reach Poland from Russian teritory.

Could it be just accident? Firing off anti-air near Poland-Ukrainian border and booster fell on Polish village? Hell maybe it was even fired of from Polish teritory in the first place, aparently Poland has few of these aswell, did they just bombed themselfes?