Don't know if anyone else is experiencing this, but I often will tab out during game play to check things on my browser. I have noticed that when you surrender a battle, if you tab out right after clicking "ok", when you come back in the wild pet you had just engaged will still be there.
If you screw up and have the wrong pets or have a friend that needs something this may work for you, since the log out thing doesn't work any longer. Don't know if it works every time... but happens a lot to me when I am playing.

