The fact that Saul ordered his servants to go and speak privately to David, suggests that he did not speak to him face to face. However, it may also be that he did speak with David face to face and that David was somewhat wary.1 In response, he then sent his servants to go and speak further with David in private to convince him to take up the proposal.
20 Now Saul’s daughter Michal loved David. And they told Saul, and the thing pleased him.