Flood the area with posters with photos. Walk around and talk to everybody, wachis, gas station attendants, shopkeepers, anybody who is always around the area. The chisme telegraph is more effective than any CCTV and works in apagones.
Put ads in several of the newspapers that are delivered free in the area. Look at those papers to see the format people use to advertise lost and found dogs.
I have seen these work in my neighborhood. People who lose dogs who get very proactive, creative and tenacious increase their chances of finding the dog exponentially.
Many people will take in a lost dog who is obviously someone's pet in order to protect it while they wonder how to find the owner. Do their work for them.