I would never EVER have someplace train my dogs without my supervision. My dogs go to daycare when we are gone for more then a day. All they do is play play play! No cages no punishment.
Although training is important as a puppy, I have rescued all my dogs as seniors and they are also very trainable. I would go the daycare method, he will learn how to socialize when being with other dogs.
Be sure to check out the daycare in advance and ask lots of questions!