okay, so I've been doing some more research on this, and I'm not convinced he has it. There is definitely something neurological going on, though.

He hasn't been eating for the past month or so. He's been losing weight. Assist feeding was attempted, but he regurged.
The first 4 inches or so of his neck is limp, but the rest of him seems fine. He can right himself when turned on his back, although it takes a bit longer than it should. his back half is perfect. I watched him turn over, he starts with his tail and his head, and worked his way towards the middle. I've read that they have a difficult time righting themselves, or they can't do it at all with IBD, and that its the tail end that loses motor function, not the neck.
He does respond to sudden movements and such. His pupils respond normally to light.

The timeframe doesn't seem right, either.
If he had IBD, would he be getting worse? His symptoms started a month ago, and have not gotten better or worse. He's the same as he was when the symptoms started.

Any info is greatly appreciated. We are trying to scrounge up the money for a vet visit, but things are really tight right now. He's probably going to end up in the freezer soon, as he can't eat, and isn't going to get better.