Actually Picard tells Durken they thought the Malcorians would react negatively to first contact. They know that because....they studied them.![]()
I actually forgot about that part.
Which would bring you around to the question of why the Federation hadn't pulled up camp and left the Malcorains alone long before the incident with Riker. The longer you have people on the ground the more likely a mistake, like what happened, becomes.
A controlled first contact is, like Picard says, far better than a random encounter in space.