Exactly. Had that been anyone else (like say a Bodie or a Snoop), they would've went through with it. If you remember when Slim and Cutty was gonna do that hit on Marlo but them lame niggas fucked it up, Slim abandoned ship rather than just go through with it. Also, Slim never said no to Stringer when Stringer asked him to kill Davis, he spoke against it, but didn't decline until Avon told him he didn't have to do it. Even though he knew it was stupid, he would've still done it had the boss told him. Furthermore, when Omar hemmed him up in the hallway, he still wouldn't give up no boss and told Omar to do what he had to do. Definition of a soldier. The only move Slim made on his own was killing Cheese.
On a side note, Stringer was still planning on having Clay Davis killed and was gonna hire out of town killers to do so.