Put up flyers. We have a constant visitor I have dubbed "Charlie" that sleeps on my porch or in my shrubs, even lets me pet him or comes and sits with me while I am planting flowers. I am mindful not to feed him so he will go home because being a friendly guy I know he must be a pet (no collar). Maybe someone found Zorro and started feeding him since he is a pet cat and was friendly to them? Wishing you the best, we had a cat Sylvester growing up that would disappear for weeks it was so stressful but he came back.