[Felina]

You can call anonymously to Animal Control to complain or you could also try sending an anonymous letter if you don't want to call (to them and/or to Animal Control).

Here in Jacksonville I've filed a complaint against my neighbors dogs for digging under my fence and had to get it notarized for his case file. I guess it takes three notarized statements for Animal Control to take my neighbor into court for not caring/controlling his dogs.

Are they renters where you could contact the landlord and advise him of the situation?

Maybe send some anonymous dog care information to these people so they know how to treat an animal.

Do you have somewhere safe to take him if he digs into your yard again -- Cody deserves a loving home.

Good luck.