Of course he can. That's why it's an endorsement. He can suggest anyone he likes.
But that would involve holding him to any kind of standard of conduct whatsoever, which I know you have a problem with.
I guess you believe in winning at any cost. Trump has a lot of sway in Alabama. He's one of the only people who could make a difference, and at one point, it seemed like he was going to use that power.
Where's the omelette?
It will be an Alabama Omelette. Not what Trump would have ordered, but what they wanted down there. He doesn't lose anything by endorsing him, and the witch hunt makes it easier. If he doesn't endorse him and Moore wins anyway then he's got a fire brand that might try to make some dumb point somehow by not voting Red. If he endorses him he can have some sway by reminding him of that, and it's not like he's going to get any of his loony tune stuff thru.