True, Amara didn't tell Drew about the bruises, although he had promised Drew he would talk to him about what was going on and I don't think he would have been able to do that without showing him. It takes a lot of courage though to bring up something like that and I think, whether subconsciously or consciously, he gave Drew the clue about the bruises without having to come out and say it. Amara was across the table from Drew, so he wouldn't have been able to push the sleeve up all the way from where he was sitting. He would have had to get up and walk around the table to do that. I think he would have been aware that in this situation Amara wasn't up to having someone invade his personal space, even if it was Drew. After all they're not THAT close. He'd seen enough and he acted on it.