Oh no poor little guy...that's probably what happened the first time...he just darted away, although, the original owners weren't as fortunate to find him again..
Glad you were able to find him.
I'm surprised with all the ads going around in CA of lost yorkies & families looking for them that nothing panned out for the little guy. Thank goodness he was lucky enough to find a nice warm home to take him in...
If I remember correctly, you should not be solely giving him wet food as his only diet(other than raw maybe?). I do believe they need some dry kibble also for a balanced diet. You may want to post a thread in the health & diet section. I know they can be finicky but we as the mommies have to make sure they are getting what they need.
You're doing a good job so far though to have this unexpected puppy ownership thrust upon you.