I wanted to post one last time. With a heavy heart, I did return Caribou to the shelter where he came from. I sincerely thing he needs a place where he can have some time outdoors, which may help with the pooping issue. It may also be better if he's with someone who's had cats before and can work on this issue better than I. In the meantime, I'm focusing on my dumpster kitten, who has become depressed due to his leaving. He seemed very happy to be back at the shelter and definitely acted like he owned the joint as soon as he walked in again.