It was said by Posel Gajewska on Polsat News. Her whole appearance was full of election talking points so its not like she went off piste and was not saying anything PO would not approve of.
Gajewska said no such thing. She only said that
she won't be there at the military parade, she didn't say anything about the rest of PO or any "boycott". The host asked her if
she's going to attend and she said that
SHE won't. You've drawn some wild conclusions based on that.
And then former PO Posel Mucha
...said that she will take part in the celebrations in Lublin.
adds her inteligent opinion, saying only authoritarian regimes have nice military parades.
You're lying again. She didn't say that "only" authoritarian regimes have nice military parades. She said, I quote:
"Don't you have an impression that the more authoritarian the government is, the bigger military parades it organises?"
She does have a point. Besides, not everyone has to be into military parades. Not everyone in the army is a fan of military parades and "military demonstrations" for politicians either, btw.
Also, Anna Mucha is in Polska 2050 now, not in PO.