I am so glad you found her and she is home safe and sound.
AJ and Merlin were both kept outside before we rescued them - they both dart out the door given half a chance. AJ spent many a single night outside after getting under one of the dogs and walking out with them, all being black I didn't see him sneak out with the dogs. Merlin does it now as big as he is you would think I would be able to see it is a cat and not a dog, plus he is gray. Thankfully Merlin has never spent the night outside he is such a scardy cat I don't' know if he would come home to me or take off. We tried the water bottle but it didn't seem to faze them. Tucker has gotten out once I didn't realize he had followed me into the garage when I was taking down the trash but the next door neighbors cat put him running back inside. You can open the door and Penny will just sit looking around, I think she knows she is better off inside then out. We do a head count now before going anywhere.