Well, we took a trip to the vet, and she said there is nothing wrong with him outwardly, and in fact is rather a healthy boy, but did notice a change in behavior (she's the same vet I brought him to when I first got him and when they had their myco flare-up). She's not a "rat psychologist" (her words) but she suggested a same age friend STAT esp. if he is not taking to the babies and he keeps on like he is. I'm not so sure about that. I'm worried I'd end up with TWO lone rats and a happy pair, or a happy trio and a still unhappy Denny. *sigh* I'm going to keep on keepin' on with the babies, though. Eventually he has to like them, right? :?
I had her check over the babies, too, since I was there and they don't charge extra for multiples anyway, and they are also nice and healthy. She was impressed at how licky Preston was.