Happy to check once it's live. One thing now, so you don't have to fix it twice.
I re-read all five PNGs on your page today. All five still carry the eXIf chunk with a bad CRC, including the new header image, which went up after my first reply. So the old files aren't the only problem. Whatever step exports them writes the broken chunk each time, and re-saving through that same step will bring it back.
A fix I tested on your header image: magick in.png -define png:exclude-chunk=exif out.png (ImageMagick 7). Pillow then opens it and every chunk CRC checks. The same pass also drops your caBX (Content Credentials) chunk. Your page already has itch's AI-Assisted disclosure, so whether you keep that chunk is your call. Just know it goes.
When the update is up, post here and I'll re-run the same checks: CRC, Pillow load, and edge margin.