Finding Gynvael's hidden cats

I'm sure you're watching Gynvael's youtube channel (https://www.youtube.com/channel/UCCkVMojdBWS-JtH7TliWkVg) and read his blog at http://gynvael.coldwind.pl.
He left a note on his blog.

Here's my attempt to find his cats.
https://gist.github.com/fritzfs/cb06d43b55bbbb5d2d2b3934d2ca2f34