I'm sorry.
You really did do the right thing. Hey...if you remember the phone number or anything...just give them a call...let them know that if Chiki ever becomes to much for them or whatever, then you'd be happy to take him. Or if you see him wandering again...
It reminds me of a couple months ago what happened to me. I was at my aunt's house babysitting my cousin, and this beagle wandered into the front yard. She was in good condition, friendly, etc., but she had no identification. I did everything I could (while still needing to be responsible for and watch my cousin) to find this dog's home while I was at my aunt's house. I called every shelter, vet, etc., I could find. I took her around to 2 of the neighbor's houses asking if they recognized her.
I put her in the backyard and waited until my family got home to go out with her to find her owner. I got to this one house, and the woman told me the dog's name was Angel and she lived next door, "but she hates it there." I took 'Angel' next door, and when the woman answered the door I asked her "is this your dog?" and she just went "yeah, thanks." and took her inside. She said her kids were wondering where she was. I was like...OMG...your dog has been missing for like 6 hours. No one was even out looking for her.
I had a yorkie, Maddie, who ran away twice. Both times we had hundreds of fliers out within an hour. I don't understand how people can just...not worry...when their dogs are lost.