Duct tape was George's. It could have been his idea, a former police detective, to make it look like a kidnapping instead of the coverup of an unfortunate accident they were all afraid to let CA in on the truth of.
I don't get the hang up on the duct tape being George's. The defense said follow the duct tape. So what if it was George's duct tape. Casey lived at the house and could get and use the duct tape. I'm sure the laundry bag was Cindy's and no one is blaming Cindy for dumping the body because the laundry bag was hers.
Next time I eat the last brownie, I'm claiming dh bought it, therefore they were his, therefore he ate the last one.