Any concerns with a hashgacha should be aired with the rav hamachshir first, not the coffee room. If the answers of the rav hamachshir dont sit well with you, (or even if they do), speak to your own Rav, not the coffee room. The Chaf K is a sponsor of the CC Heritage Foundation Tisha Bav Shmiras Halashon videos and their tag line is be as careful with what comes out of your mouth as what goes in. Was the Rav Hamachshir contacted? Did you consult your own Rav?
Wait a second, NO Pizza shops in Krakow? Was there at least a Sushi place?