Cosmo showed up this morning! Still looking - not very happy with us - but improved! We're positive he didn't belong to anyone as feral as he was, and in the condition he was. Hopefully with all mats removed, antibiotic shot, fixed, tested, and other shots, he will continue to improve. He's welcome in our yard at all times! He's older so I don't see a lot of hope in taming him, especially as "nasty" as he acted, but we'll care for him nonetheless!