Here's a fun story about recapturing a cali king that had gotten loose. I don't know for sure how true it is or if it was more of a popular myth, or at least greatly exaggerated.
I used to volunteer at a zoo. One of the things we got to do was take out "contact animals" that allowed zoo guests to get up close and personal and actually touch some animals. Some of my favorites were the ball pythons. There was one other snake in the contact animals, a cali king.
The story is that one of the times a volunteer had taken the cali king out, it had gotten loose. Since what was usually done with the contact animals was to walk around the zoo grounds with them, this wasn't like loose in a building, this was loose outside on the zoo grounds.
Quite a long time later, my recollection is that it was more than a year, but this was quite a few years ago so I'm not too certain on that, the same cali king, identifiable by unique markings in a slightly aberrant pattern, was recaptured, still living on the zoo grounds.
So maybe there is still hope!