Cody may have been blind, but he wasn't stupid. This podunk little town was turning into a powder keg, and the fuse was being lit. He didn't know what would make things blow, but he knew of two things that would make Dalton dangerous: hurting innocents, and hurting people Dalton loved. Wesley had already proven he didn't care about keeping collateral damage down when he burned Red's store, Cody just kept praying that Wesley wanted the Doc back more than he wanted to hurt Dalton.
Cody tried not to even think about the possibility that Wesley would go after Garrett, especially not that he might succeed. Because as inconceivable as it was, Garrett was the most important person in the world to Dalton. If Garrett was hurt, or killed, Dalton would paint the moon with Wesley's blood, even if he had to go to hell to do it.