Sorry for not getting to this sooner, I didn't see it. A heads up for the future: on Itch, be sure to reply to whoever you want to get the attention of. Here you're replying to...yourself, so I don't get a notification (just happened to be checking this thread for other reasons).
Sorry for the trouble though. I'll repeat what I said earlier: join the substar for a month if you can. I see by my analytics there that I have, or have had at least one supporter from Poland in the past, so there's at least SOME chance your card will be accepted.