Uh oh!

Well, just keep looking and hope that they return. Most dogs will (of course, unless something bad happens..let's hope not!). It's not your fault. I can almost bet that they have had the same problems before. And, it's not like you didn't try to stop them from getting out. You DID attempt to block their escape route. It could have happened to the owners too.

My mom was horse-sitting for some friends once and one of their horses died while she was taking care of them. It was old and just passed away due to age, but my mom felt SO guilty and thought that they would be mad. They weren't though..they knew that the horse was approaching its last days.