Well, I talked to a man at the Nature Center, who seemed quite happy to think that I may have found a Butler's on the other end of town! I'm going to email him some pics, and I also directed him to this forum, so he can look at the ones I've already posted.
If it turns out that his ID is confirmed, then Twister will be returned home on the weekend, and I will pray that measures will be taken to protect the area I found him in, so we can hope to someday see many more of his kind!
I've gotten over the initial disappointment of having to let him go, in fact, I'm kind of hoping I've discovered something great over at that little pond..........