Hmm Craig@bitcoin-cats.ca seems to be OK as far as I can tell. JSON looks good. Maybe a problem with the upper case C in some clients?
You might also try the nostr.json generator by nostr:npub1s02jksmr6tgmcksf3hnmue7pyzlm0sxwarh7lk8tdeprw2hjg6ysp7fxtw