CRISPR isn't magic, and the state of genetic testing is nowhere near what would be needed to deliberately introduce new anatomical features to multicellular organisms. This isn't a case of making a protein by inserting the DNA sequence that makes that protein, and even doing that is unreliable - which is fine, when you need some of your e. coli that you can breed in a day to get it and can kill the rest off with an antibiotic (generally the DNA sequence you want also gives resistance to that same antibiotic), then keep breeding the ones you want. That's less fine when you're looking at a cat, and while it is still used (e.g. medical research where GFP is used as an indicator for changes, hence glowing cats) it's less than ideal here.

In short we don't know what steps to take, but we do know that whatever those steps are the process to do it isn't there.