Look in every singal nook and cranny of the perimeter of the place. I know this sounds gross, but pee in a cup, put it in a squirt bottle and spray the outside perimeter of your house. It works. Cats have awesome sense of smell.

She also might be hurt. Check the bushes. go around the neighborhood and ask the neighbors to check any decks, storage sheds.

You'll be in my thoughts and prayers for him to come back. One last ditch effort is to go around shaking a treat back. Food is a great motivator.